Recognizing and Understanding TOC as a Systems Meta-Methodology

The mapping of the various TOC TP tools and methods to the Mingers and M-B frameworks shows that they not only overlap or substitute for each other to some degree, in terms of purpose and underlying philosophical assumptions, but that they may also be complementary in nature. Indeed, whereas we may expect similar insights to arise from more than one method or frame, in general, there may also be new insights about the problem, and how it should be tackled, arising from each.

As a result, we suggest there will be, in most cases, no one best model, method, or methodology; and as such any implicit search for a "best-fit" model or method should be surfaced explicitly and abandoned. If so, the pragmatic adoption of what may then be a multi-method or multi-methodological approach accords with Burrell and Morgan (1979) and Brocklesby (1993) in their discussion and acceptance of the efficacy of multi-paradigm and multi-methodology development.

Seldom are any of the TOC methods and tools used in isolation. Certainly, for complex problems, several tools may be, and are often used as problem-solving intervention moves through the stages from diagnosis to implementation (Kim et al., 2008). Using the conceptualizations of the M-B framework, we recognize that TOC methods are often used as complements to broaden or heighten, for example, the appreciation phase of intervention, or to complement analysis and assessment/evaluation with a stronger action/implementation phase.

When the full set of TOC tools and methods considered here are mapped to the M-B framework (see Tables 23-5 and 23-6), we note how these methods may comprise a multi-method approach, attending to almost all phases of intervention across all dimensions of the problem domain. Consequently, they can be regarded as a methodological set. We also note the potential for further discussion of whether the broad umbrella of TOC can be regarded as a meta-methodology, a meta-framework, or a multi-methodological approach. We also note the irony in the juxtaposition of the benefits of such potential discussion, and the lack of deep understanding about TOC that prevails.

Observations-A Lack of Deep Understanding Prevails about TOC

There has been an unfortunate lacuna in the TOC literature relating to the nature of methodology and of methodological developments. Consequently, there has been an absence of the necessary base for critical reflection about methodology-in-use. Invoking Argyris and Schon's (1974) notion of double loop learning which stresses the importance of reflection about experiences for learning to take place (Schon, 1983; Kolb, 1984), we would argue that TOC practitioners are no different from others in needing to be critically reflective about their experiences of using TOC. Such critical reflection is a necessary condition for a deeper understanding of TOC by its users.

One example of a lack of reflection, or of a shortcoming in TOC methodology, relates to the systemic nature of the TP. In particular, it relates to the minimal presence or relative absence of a critical component of systems thinking; that is, feedback and feedback loops. Whereas systems representations embodying CLDs actively search for feedback loops in the depiction of cause-effect relationships, the process by which, for example, a CRT is developed, linking problem symptoms in a chain of causal relations to the root cause, to some extent, mitigates against the identification of feedback loops.

In the building of a CRT, feedback loops tend to be added in the latter steps of the process, almost at the conclusion of building the tree. Moreover, such loops are typically labeled as "negative feedback loops" because they refer to the continuing and "negative" unwanted or desirable nature of the situation being described.

However, while TOC's definition and usage of feedback loops is unambiguous in the context of TOC, and used with consistency within the TOC community, such definition and usage are unnecessarily out of step with the rest of the systems community. We suggest that a change in process and definition should be contemplated by the TOC community. In other systems methodologies, any feedback loop that reinforces an effect is termed a "positive feedback loop." Indeed, in most systems methodologies, both "vicious" and "virtuous cycles" are conceptualized and labeled as positive feedback loops-the simplest example being that of two variables that act on each other in a mutually reinforcing manner-with each variable causally effecting and being causally effected by the other to create greater effects of a positive or negative nature. By contrast, a negative loop is one that moderates an effect, that brings a variable back on course in the sense that it incorporates one or more cause-effect relationships that bring a system back to a desired state, like a thermostatically controlled air conditioning system. Relabeling and redefining the TOC loops accordingly would facilitate a shared understanding and acceptance of TP diagrams, and the TOC approach more generally, by other systems communities.

Exploring the link between TOC and other systems methodologies can also enhance understanding of problem situations. Indeed, we have argued elsewhere (e.g., Davies and Mabin, 2009) that each of the EC and CLD representations can be enhanced by multi-methodological use to display relationships, not only using necessity logic, but also-with appropriate explanatory intermediate variables emanating from assumptions underlying the EC-using if-then sufficiency logic. Such examples illustrate beneficial developments in TOC methods that may be sought over time to improve TOC as a methodology, and to enhance the use of particular TP tools.

Ronen's comments (2005) also suggest that, regardless of such shortcomings, it is necessary to establish the credibility of TOC as a methodology within academia. In his early writings, Goldratt (1990b, 23) described the development of scientific theories as a progression through classification, correlation, and causation stages. Here we have provided the classificatory frameworks that form a basis for understanding how TOC TP methods and methodology within TOC are constituted.

Summary

What Has Been Covered in This Chapter

This chapter has provided an overview of the TP that has addressed their conceptual, philosophical, and methodological foundations, alongside discussion of the TP use and practice. As such, we have been able to reflect on the need for the TP; on the design and purpose of the TP; on their effective use in practice; on reasons for their existence and effectiveness; and we have done so in order to effect a consolidation of our understanding of the TP that may serve as a platform for future developments and use.

In doing so, we have provided a supporting rationale for the existence of the TP by explaining how they meet needs of a methodological and practical nature that are not addressed by other problem-structuring and problem-solving methods, for example, those of OR/MS. We have also suggested that there is a need to explore how the TP may be used in multi-method and multi-methodological intervention with, say, OR/MS or systems methods, with other TP tools, and with other TOC methods. In addition, we believe that building such links and bridges with cognate fields and disciplines through multi-methodological intervention, exploiting identified synergies, may well serve to gain further acceptance for TOC within those cognate fields, through the building of communities of practice, with, say, those embracing systems and soft OR methodologies.

Furthermore, we respond to the call for the domain of TOC practice, and for TOC as an academic field of inquiry, to gain further recognition from cognate professional groups and academia, by suggesting further engagement in research on TOC methods and practice that satisfy the demands of professional and academic rigor, open doors to highly regarded publication outlets, and to acceptance of TOC as a bona fide academic endeavor. The following section addresses these matters.

Findings and Recommendations

There is seemingly ample evidence of how diverse issues and problems can be tackled effectively using a variety of Goldratt's TOC tools, principles, and methods-from the simplistic product mix algorithm, the 5FS, Drum-Buffer-Rope (DBR), Buffer Management (BM), Critical Chain (CC), the EC, to the suite of TP (Rahman, 1998; Kim et al., 2008; Mabin and Balderstone, 2000; 2003; Mabin and Davies, 2003; Inman et al., 2009; Watson et al., 2007).

The review of Kim et al. (2008), reported here, revealed specific publication and research gaps, and some common future research topics and approaches have emerged. First, no work has been published that relates to critical success factors or necessary conditions underpinning the effective implementation of the TP. Given the empirical importance of measuring and comparing the rate of success or failure with other business improvement approaches, such as ERP, Lean, or Six Sigma, it is a little surprising that the publication of research on this topic has attracted minimal attention among TP academics. Further investigation of critical success factors and common problems in the application of the TP is definitely required.

Second, in order to provide practitioners and academics with a critical evaluation of TP tools-in-use, the lack of published empirical work on the effectiveness of TP applications must be addressed. Inman et al.'s (2009) cross-sectional analysis, using structural equation modeling, to examine the links between elements of TOC use, TOC outcomes, and organizational performance has provided illustration of analysis not previously attempted, as a means of filling such gaps. Further empirical studies of both cross-sectional and longitudinal nature, across industries and applications, and over time, would be appropriate, in as much as they would promote the testing of research hypotheses and would strengthen the TP knowledge base. In particular, such research could be directed toward identifying and measuring performance before and after TOC implementation.

Third, the literature reveals an ongoing discussion and critique regarding the philosophical underpinnings of TOC as a methodology. One apparent limitation with the use of the TP is that their use appears to be problem driven; they are applied only when there is a "problem" (Tanner and Honeycutt, 1996; Antunes et al., 2004). The review suggests that there is an unmet need for studies exploring how TOC methods can be applied, not just in problem situations, but also in situations that are problematic in a positive rather than a negative sense. This approach reflects a paradigm shift that has been termed "'blue ocean" strategy. Kim and Mauborgne (2005) argue that most companies need to create blue oceans of opportunities. They show how a company can create a blue ocean by changing its strategic thinking and using a systems approach. As such, Kim et al. (2008) recommended that more consideration should be given to how the TP could be applied in situations where positives are renewed and advanced, rather than just responding to negatives, or to a need to eliminate or ameliorate problems. The recent development of S&T and their application in situations where "stretch" strategic goals may be set, either to ameliorate or eliminate negatives or to pursue positives, would appear to address this gap. S&T trees were not found in the peer-reviewed literature, but are discussed in Chapters 15, 18, 22, 25, 31, and 34 in this volume.

Furthermore, the overview presented here suggests that there is scope for building on the considerable work that uses the non-TP part of TOC, to test the impact of using the TP in addition or as an alternative to the non-TP tools. Many non-TP examples were documented in Mabin and Balderstone (2000), while a recent example, Pirasteh and Farah (2006), documents a study combining TOC's 5FS with Lean and Six Sigma with remarkable results. One wonders whether the results would be significantly different if the TP were used, rather than just the 5FS. Thus, further investigation relating to the methodological appropriateness of different combinations, or sequenced use, of TP tools in specific situations is desirable, as has also been suggested by Dettmer.

It may also be worth investigating whether the conventional sequenced use of TP tools should be followed "blindly." While Dettmer (2007) promotes sequenced use of the TP tools, Schragenheim (1999) advocates a freer form of diagramming using the principles of the TP logic without confining it to specific diagrams. In addition, the TP tools can also be used individually to improve performance in a variety of situations, while many different combinations of TP tools used in different orders have been found to be effective, as reported in the literature (see Tables 23-1 and 23-2). It could be helpful to identify the circumstances in which particular combinations or sequences may be most effective.

Ronen (2005) has issued the challenge to TOC researchers to confirm and improve TOC methods and apply academic rigor to TOC-related research and research on TOC. In this chapter, we have drawn on our classificatory examination of the philosophical underpinnings of the TOC TP and their relationship to different phases of problem solving (Davies et al., 2005) to show how such tools and methods purposefully attend to different issues and surface different insights, using different kinds of information sourced in different ways. We have shown how the choice and use of a TOC TP tool reflects, in essence, a deliberate attempt to represent, frame, or model a problem situation in a certain way, each representation being used with specific intent, thereby highlighting certain aspects while downplaying or ignoring other aspects. These matters are reflections not only of what the tool or method is intended to do, but what it assumes to exist-its ontological base-and the nature of what is represented or modeled, with what kind of information; that is, its epistemology. Consequently, we also see value in research that embraces such philosophical and methodological foundations to consider future developments of TOC methodology that may occur (1) via evolution of new tools, for example, new TOC TP; (2) via those tools that have yet to reach the peer-reviewed public domain, such as the S&T trees7; or (3) via the development of new application areas. Such research would need to embody the academic rigor necessary to build the academic stature of TOC.

We also see value in research that addresses shortcomings of the TP, as for example, the surfacing, representation, and definition of feedback. In addition, research that targets new classes of problems and applications would be welcome, as would research to address matters of practicability and ease of use. Related research that seeks to aid reflection and learning about TOC methods-in-use, reasons for success or failure, etc. would prove useful for practitioners and underpin longitudinal work on the effectiveness of TOC tools and methods. Similarly, research that explores the psychological and technical barriers to the use of TOC TP tools would not only benefit practitioners, but also contribute to the development of strategies and resources for teaching TP in the TOC for Education8 program. Finally, given such an extensive agenda, there is a related need to coordinate such research efforts if they are to add to the TOC body of knowledge.

The classificatory mapping of the various TOC frames, models, and methods to the Mingers and M-B frameworks shows that they not only overlap or substitute for each other to some degree, in terms of purpose and underlying philosophical assumptions, but that they may also be complementary, not only in nature, but also in terms of insights generated about the problem. As stated elsewhere (Davies et al., 2005), the recommended pragmatic adoption of a multi-method or multi-methodological approach accords with the views of Burrell and Morgan (1979) and Brocklesby (1993) in their discussion and acceptance of the efficacy of multi-paradigm and multi-methodology development.

Our reviews of the TP literature show that seldom are the TP tools used in isolation. Certainly, for complex problems, there is evidence that several tools may be used as problem-solving intervention moves through diagnosis to the implementation phase. Such multi-method use is in keeping with the findings of analysis using the M-B classificatory framework, where we recognize that TOC methods can be used as complements to broaden or heighten the appreciation phase of intervention, or to complement analysis and assessment or evaluation with a stronger action or implementation phase.

Indeed, when the full set of TOC tools and methods discussed are mapped to the M-B framework (see Tables 23-5 and 23-6), we note how TOC methods comprise a comprehensive multi-method approach, and can be regarded as a methodological set, a multi-methodological approach, a meta-methodology, or a meta-framework. We also see TOC and the TP tools as offering a complementarity that others have sought through the development of multi-method and multi-methodological approaches combining hard and soft OR methodologies and methods (Davies et al., 2005).

TOC can be described as a methodology that offers methods that embrace the whole range of activities or phases from problem identification and representation, the setting of appropriate objectives, generation and evaluation of alternatives, through to implementation. In forming this view, it has been instructive to surface and clarify the various activities embraced by TOC (see Table 23-6), as well as the nature of the philosophical assumptions, ontological and epistemological, that underpin the various methods and tools that make up TOC (see Table 23-7).

As previously noted, various authors have identified elements additional to the familiar TOC questions of What to Change?, To What to Change?, and How to Change? Research is needed to explore further all phases of problem-solving that contribute to improvement in organizations, to go beyond the What to Change?, To What to Change?, and How to Change? questions and phases, and to extend these questions to include and begin with Why Change? and to follow them with How to Sustain the Change? and How to Establish a Process of Ongoing Improvement (POOGI)? Articles defining these elements and logically connecting them as a system for improvement would be of value. These questions are, of course, preceded by questions relating to: What the System is, What the System Goal is, and How Progress Toward the Goal will be Measured.

As such, our analysis has helped clarify the potential supplementary or complementary role of the TP tools in relation to traditional OR/MS methodologies and methods. In a general sense, we have commented on the seeming equivalence between TOC TP and soft OR methodologies like SSM. In particular, we have noted the equivalent roles filled by rich pictures within SSM and the CRT within Dettmer's (2003) broader use of the OODA process for strategy development. As such, there is much to be gained from reconceptualizing TOC and the TOC TP as being within the broader domain of problem-solving methodologies such as OR/MS, or within the specific domain of soft OR, not just as an academic discipline worthy of study, but as a meta-methodology that offers a set of methods for use alongside traditional OR/MS methods and other PSMs.

TOC methods have yet to be fully understood or endorsed by the OR/MS community. Similarly, we suggest that TOC methods have yet to be fully understood by the TOC community, in terms of their philosophical underpinning, their systemic nature as a multi-methodological set, and their multi-methodological use with other OR/MS and systems methodologies. The TOC community has yet to identify with the OR/MS and other kindred communities. Yet TOC embraces and can be embraced by OR/MS and soft OR. A next step is to continue to build awareness of such complementarity, and to understand more about how and when a multi-method approach can be used best.

As such, we see benefit in future research addressing multi-methodological issues, not just identifying the potential for combining methods in multi-method or multi-methodological use, not just in combining methodologies in multi-methodological use, but also assessing and clarifying the philosophical and methodological assumptions that would underpin methodological consistency and rigor in using TP in harness with other methods and tools. For example, the notion of problem templates or archetypes is well founded and accepted in the systems world in terms of identifying common systemic structure in problematic situations using CLDs (Senge, 1990; Wolstenholme, 2004). Thus, there may be merit in exploring and developing archetype clouds for archetypical dilemmas, and in the development of archetypical solutions or solution processes.

Links to Other Chapters in the TP Section

The discussion in this chapter may usefully shed light on the nature of other TOC tools and methods, their use in multiple problem domains, and their potential for use in multi-methodological intervention. As a consequence, links to other chapters may prove fruitful in focusing attention on the purpose of design, the purpose of use of the TP tools, and the other philosophical assumptions that are made about cause-effect relations, how we surface them, and how we represent them in the particular forms that are manifest as the logic trees, a belief in the existence of root causes, etc.

In addition, having demonstrated the nature of the suite of TP logic tools as being a comprehensive methodology or meta-methodology, the classificatory frameworks used in doing so may be used to shed light on the efficacy of different TP tools used in combination with each other, or used in combination with other non-TOC tools or methods, or subsumed, for example, within the OODA process developed by Dettmer (Chapter 19, this volume) to surface strategic issues and goals. Similarly, they may be used to shed light upon the S&T tree (as in Chapters 15, 18, 22, 25, and 34 in this volume).

"Once you have solved someone's problem, you have forever blocked them from inventing those answers for themselves."-Goldratt (1990b, 18)

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