In TRANSYT 14 up to the latest version (TRANSYT 17), running a full optimisation run twice (and also repeatedly) in TRANSYT producing better results is nothing new to TRANSYT, and is simply due to the optimiser being given a second or extra chances to determine improved timings. With the AUTO REDISTRIBUTE option (aka EQUISAT) switch off, the optimised timings from one run automatically become the starting set of timings for the next run. If they are different from the previous timings then again the optimised results from this run can again be better. N.B. This effect will never produce worse timings than the previous run. This procedure can be automated by selecting the “Use Enhanced Optimisation” option within the “Advanced” section of the Optimisation options.
Furthermore, regarding what is said above regarding different starting points, an optimiser called “shotgun hill-climb” exists in TRANSYT. This allows multiple runs of TRANSYT to be carried out, each with a different starting point (in terms of timings). Since the starting point can have an influence on the final timings, this allows TRANSYT to produce better timings for those who are happy to let TRANSYT take longer to produce a set of results. This feature is described in full in the TRANSYT User Guide.
(Updated April 2025)