If I understand your "think time" thing, you are taking items off the "think list" for so many cycles if they are not hyperthinking. In other words, you have a list of items that you must go through each cycle and let them think. If an item slows down its thinking it is merely off the list for a certain number of cycles.
That would mean you have to check the items off the list to see if they are ready to get back on the list, so maybe Zith is correct, you have to chack them all every cycle.
As I remember, to get an advantage from putting a fork (or any code section) to sleep you have to have a hardware timer or some such thing keep track of when to fire it back up or else you are just polling again.
Did I get it????????????????
hehe
VG