Ref: Lindblom, J. E.; 'The Science of Muddling Through'; Public Administration Review, American Society for Public Administration, Washington, DC, Vol. 19, Spring 1959, pp 79-88
Linblom argues that while the 'Rational-Comprehensive' (root) approach is much discussed as the 'way it should be done'; this approach is rarely practical because of the ongoing nature of activities. He argues for what he describes as 'Successive Limited Comparisons' or (branch technique). This second approach more closely matches the conventional Engineering and Development process which proceeds toward successive improvement, rather than trying to study the whole of the solution set, and search for the optimum.
Two possible Approaches are outlined below for policy analysis. One can substitute design, or action, etc. for policy in the following table to clarify the meaning for particular circumstances. The essential differences between the two approaches are that the 'Rational - Comprehensive' implies that the decision maker postpones the final decision until the complete analysis and comparisons are made, while the other technique implies that decisions are made during the progress of events.
In engineering terms the first approach implies that the design is
complete before construction begins, while the second suggests that
only enough of the design will be done to allow construction to begin,
the remainder will be selected as required to maintain progress.
The second technique tends to be used during the engineering design and
many other processes where its is impractical to keep all options open
until the the very end.
| Rational - Comprehensive | Successive Limited Comparisons |
| 1a. Clarification of values or objectives distinct from and usually prerequisite to empirical analysis of alternative policies. | 1b. Selection of values goals and empirical analysis of the needed action are not distinct from one another but are closely intertwined. |
| 2a Policy-formulation is therefore approached through means-end analysis: First the ends are isolated, then the means to achieve them are sought. | 2b. Since means and ends are not distinct, means-end analysis is often inappropriate or limited |
| 3a. The rest of a 'good' policy is that it can be shown to be the most appropriate means to desired ends. | 3b. The test of a 'good' policy is typically that various analysts find themselves directly agreeing on a policy (without their agreeing that it is the most appropriate means to an agreed objectives). |
| 4a. Analysis is comprehensive: every important relevant factor is taken account. | 4b. Analysis is drastically limited:
(i) Important possible outcomes are neglected. (ii) Important alternative potential policies are neglected. (iii) Important affected values are neglected. |
| 5a. Theory is often heavily relied upon. | 5b. A succession of comparisons greatly reduces or eliminates reliance on theory. |