The answer to this one is complicated.
The short answer is that for some modules, you can, but it's not really recommended.
The long answer is that it depends where these modules draw their data from. As you may or may not know - StarTools keeps your data in a super position; that is, simultaneously linear and non-linear, deconvolved and non-deconvolved, wiped and non-wiped, etc. By being able to draw data from at its best possible state (for example deconvolution needs linear data) ST can produce better results,
seemingly allow things that don't make sense mathematically (e.g. decon of non-linear data), while also being able to track signal vs noise evolution.
For some modules, there is a complex interplay between what went before and what went after when StarTools tries to insert an operation in the "right moment in time". StarTools tries to make sense of it all and, as a result, bad/crazy sequence choices tend to still give reasonable results, rather than quickly turning the image into something "overcooked" as would be the case in other, linear software.
Running Decon multiple times will just redo the Decon, rather than applying it again. That's because Decon is meant to be applied only once. Same thing for color calibration (the colors start from scratch rather than building on what any previous iteration of the Color module would have done). Contrast/Wipe will do much less if repeated, and the same goes for Wavelet Sharpening.
The only module that makes some moderate sense to repeat multiple times is probably the HDR, but only if you have distinctly different HDR problems.
The moral of the story; less, really is more.
