My Tellah usage second time around is:
Kill him first fight so he stops sucking experience.
Revive him once the kids have stoned themselves.
Wow, that's probably pretty effective. That gives Cecil and Yang a bit of a boost before the Magnetic Cave. I'll have to try it next time. :)
I avoid doing that simply because I need Tellah to stand up right long enough so I can kill all 3 monster-infested treasure chests at Eblan.
Bah, Cecil and Yang can do enough damage themselves... if you're nuts like me and wait til Palom has the -ga spells before you leave Mt Ordeals...
It's fun to annihilate the first form of Scarmiglione (and his horde) with a single shot of Quake, and even more fun to annihilate the second form with Firaga. Not to mention Quake on Baigan and Thundaga on Cagnazzo...
You're nuts, but I did that once before... learning tha -ga spells for Palom. I stopped doing that because the random grinding for a Lilith Rod and Cursed Ring is not worth my sanity, so I settle for just Quake. (Although, I learn Quake before I step foot into Mt. Ordeals, yay power peninsula! Pray for the random CatClaw)
I have like one actual expectation of Tellah.. to cast one useful spell per battle.. assuming he gets that chance.