I personally set up a suit of armor that also reduced restoration by 100% at the same time and cast healing hands and flames or frostbite on the same wolf on novice difficulty for a few hours and got to 100 that way... Had the added effect of raising restoration to 100 at the same time... There's also the option of the Oghma Infinium glitch but I always feel more of a sense of accomplishment when I raised my skills by actually using them in some way... Of course I only use destruction magic for the trap rune spells because they are entertaining but I did make lvl 81 legitimately... Also get married for the lover's comfort bonus as it's 15% instead of the 10% from well rested... And destruction takes roughly forfreakingever to level no matter how you do it... I didn't notice gaining any levels faster with higher level spells for some reason though I did it on patch 1.1...
And as far as the dual casting goes I believe you get more exp if you cast in one hand and then the other hand...
Me too, I don't want to use glitches. Mmm, I see. Well thanks for the info!
I've trained it a few times but I don't really understand how it works. I've trained it up 5 levels with two people, an expert and master trainer I think. It doesn't seem I can train it up any more though.
All the stuff that those guys above me said, but use Shadowmere as a "training partner". He's perfect for it.

Who's Shadowmere?
EDIT: I see, I killed Astrid though so no Dark Brother Hood quests for me.
Dawnstar torture chamber, perfect for destruction and restoration training zap the crap out of them then heal them up, rinse and repeat its a 2 for one special
Haha, I'd rather not torture them lol, I would feel guilty
