Trying to derive a negative adjustment to PC in order to keep the internals of an AIM program in line with the action taken (Stop Loss execution) is a reasonable concept IMHO.
Of course one may also reasonably ask why you need to make the adjustment to PC in the first place? After all, Lichello does allow for a swapping of one security with another at any time, provided the relative ratio between stock value to PC isn't altered too significantly. In other words, if the one you want to take a loss on one that has declined to say $10,000 worth, and to preserve what's left, you cash out the $10K, then all you should have to do is either add a new holding for $10K or add the $10K to the existing holdings. (If AIMing in a portfolio mode). That way the stock value remains where it was (more or less) and PC shouldn't be affected at all.
Or do you have something more clever afoot that we're all still missing?
Best,
AIMster