I'm getting confused.....
Foiling after the butts are pulled off the pit or foiling before they reach the temp to take them off the pit, or both?
Just curious, since the only time I use foil is when I take them off and put them in a drip pan. That's covered with foil and a heavy towel, while the butt rests.
Since the butt was both mushy and clinging to the bone, there's the possibility that one side cooked faster than the other side, especially if it was near the firebox. Was there a difference in the internal temps when checked from various places? FWIW, I usually double check the probe with an instant read and check in a couple of areas of the butt.
BTW, thought about another possibility for mushy pork. Often the ads now state "previously frozen". If it's frozen twice, that could result in a substancial (sp) texture change.
Another thought with pork. The expiration dates on pork, chicken, and fish are probably set barely before the threshold for becoming unfit for human consumption. They seem to be awfully long to me, if I happen to be there when the meat goes into the display case. That brings up the thought that in the case of pork, if it's near the expiration date, will that affect the texture, when compared to one as fresh as we can get it from a supermarket?
Just some speculations on the why.