This whole BPA/need theory is pointless, stupid, and pre-mature.
The problem with the BPA thing is too many think it is an "all or none" proposition. It isn't. BPA is usually part of a much more complex strategy, a combo of need, BPA, VORP (value over replacement player- that is how big is the drop-off between a guy at position X and possible guys at same position one round later?), and depth of class at position next year.
If Barkley drop to Washington and he's the BPA do they take him? Heck no.