Babybacks don't use the 3-2-1 method. I have seen 2-2-1 or 2-2 or some variation of that for babybacks. I am guessing you just cooked them too long but you didn't say the temp you cooked them at. That could be part of the problem as well.
Homemade Wood Smokehouse, Charmglow gasser, Smoke Hollow, UDS, dual chamber homemade grill
Certified MOINK Baller
We're surrounded. That simplifies our problem. - Chesty Puller
We will not tire, we will not falter, and we will not fail.
George W. Bush, Speech after 9/11 attacks
Scrap Iron Chef