With the changes made to faster EXP and higher EXP on quest rewards the standard method might prove to be a viable option.

It has me thinking now if I should level my alts up the normal way, it might be more enjoyable. I do level them from 58-70 in the Outlands but I think your right on the whole synergy of it. If I'm powerleveling with a 70, I'm playing that class and not the one I want to play which would explain why I stop so many times.