I am sure you can over cook crabs, but from my findings, it is not as critical as we all thought (me included) if I hadn't of found the nipper in the pot, I would have still been waiting by the timer and rushing to get crabs out of the pot and into the cold water so they do over cook, when in fact, there seems to be plenty of time. Next time someone else is cooking a few, do the same test to make sure mine was not just a "one off"