since you're talking about attaching data logic procedures i presume you're talking about dynamics, although from what i remember attaching dlp's can also be done with recent versions of adm, mostly, for compatibility with dynamics.
imo, the bigger problems with adm and dynamics or maybe big frameworks in general, i've seen are
1. they're set in their ways, sort of speak. they've got a certain way of doing things that makes them rigid or hard to do things they're weren't designed to.
2. and the flip side of having all those built in features is lots of complexity. don't get me wrong its great to have all those tons and tons of features, functionality and options to choose from but its so complicated and theres so much you'd need to know about the framework in general and every particular object if you needed to override or do something more complicated.