I gotta say.. I agree. IF the pork collar/collar butt/petite boston butt is a trimmed boston butt it's perfectly legal.
We use full sized Boston Butts and don't even trim much, but I would have zero heartache is someone wanted to use one.
If the cut comes from somewhere else, other than the butt end of a shoulder, then it would be illegal.
Would be nice if we could get some input from a board member.
4000 sq inch Wood Burner named Brutus - KCSB member/judge# 32129