STEP 3: DO IT TWICE
After documentation, the second most important criterion for success revolves around whether the product is totally original.
If the computer program in question is being developed for the first time, arrange matters so that the version finally delivered to the customer for operational deployment is actually the second version insofar as critical design/operations areas are concerned.
Figure 7 illustrates how this might be carried out by means of a simulation.
Note that it is simply the entire process done in miniature, to a time scale that is relatively small with respect to the overall effort.
The nature of this effort can vary widely depending primarily on the overall time scale and the nature of the critical problem areas to be modeled.
If the effort runs 30 months then this early development of a pilot model might be scheduled for 10 months.
For this schedule, fairly formal controls, documentation procedures, etc., can be utilized.
If, however, the overall effort were reduced to 12 months, then the pilot effort could be compressed to three months perhaps, in order to gain sufficient leverage on the mainline development.
In this case a very special kind of broad competence is required on the part of the personnel involved.
They must have an intuitive feel for analysis, coding, and program design.
They must quickly sense the trouble spots in the design, model them, model their alternatives, forget the straightforward aspects of the design which aren't worth studying at this early point, and finally arrive at an error-free program.
In either case the point of all this, as with a simulation, is that questions of timing, storage, etc. which are otherwise matters of judgment, can now be studied with precision.
Without this simulation the project manager is at the mercy of human judgment.
With the simulation he can at least perform experimental tests of some key hypotheses and scope down what remains for human judgment, which in the area of computer program design (as in the estimation of takeoff gross weight, costs to complete, or the daily double) is invariably and seriously optimistic.
Figure 7. Step 3: Attempt to do the job twice - the first result provides an early simulation of the final product.