My Aldo is consistently 600-750 and Succor is consistently 300+. Far from useless.

I think scholars start off at a disadvantage with WHM initially. However, we grow at an exponential rate due to shield mechanics. The gap closes once you get to AF2 gear. Yes, it's still not the same but I don't think that's a particularly concerning issue. A scholar is there to make the WHM more efficient. Lessen the need for over heal (and as a result unnecessary aggro gen).

Whether or not sch/sch or whm/sch or whm/whm is all equal seems rather besides the point to me. The fact that sch/sch sucks doesn't raise the issue of balance to me at all. Whether or not you need a scholar is a legitimate conversation, much along the lines of the paladin vs. gladiator discussion. I personally like them for the group efficiencies. When played right, it should make the tanks job much easier and alleviate the over heal issues from WHM. That alone, is worth quite a bit.