True that. And to address Craig's question, I don't know if there is definitive research on whether the addition of isolation movements is beneficial or detrimental to elite performance. Coming back to the PL'ing story the WSBB guys use a load of single joint assistance work...and loads of variety. These guys have a modicum of curls and flys and not much variety:
http://www.butenko.org/workout.htm.
This brings up another topic I find interesting which is specificity vs. variety. Steve mentioned a nice distinction between the conjugate method and block method based essentially on training age. If anyone is game for hashing out that topic in another thread lets get to it!