Originally Posted by Smoothsmoke
Not all butts are created equal. Some probe tender at 195 others at 205. Therefore, temperature is just a tool to let you know when to start probing. It is done when it probes tender, not by temperature.
I understand what you are saying about cooking it longer but what I found odd was that at first it was probing nicely. As the cook continued the probe started to insert harder and the more time that went by the harder it went in.
It was as if the meat was tightening up instead of getting more tender.