As I already mentioned, it is quite well possible that at some projects it does not work well. I know nothing about SIMAP, but can imagine it could be the case if the project reports the estimated value too high (theoretical maximum), and the client, at practically all WU's, aborts the unit before completing, when it finds the final result or another stop condition prematurely. If no unit is completed, the client has no chance to estimate the full lenght, and starts considering the short aborted units for full ones, claiming for them the full credit. In such case only calibrating with a reference unit of a known value would help, but since I have such unit just for S@H, I am afraid it would not be easy. I might create some empiric table with additional coeffcients for such improperly behaving projects, but it may be rather difficult too, especially because I do not participate in too many projects and do not know the behaviour of all of them.
I'll probably add a table with some limiting values for individual projects later, but may need help of bigger amount of users participating at all those projects, to collect the necessary statistical data.