Titus, you're confusing Meteor with Supernova. Supernova is the summon he uses in the final battle. Meteor is the giant rock that hits the planet at the end of the game. Between the time that Sephiroth actually summons Meteor and the time that Meteor actually hits the planet, Cloud and his party engage in possibly weeks worth of activities. There's no way it could be used in this fight.


Because, Titus, there is no way to gauge how long it takes Sephiroth to cast a spell. You never actually take full control of Sephiroth at any point in the game, and therefore you don't know if while he's being attacked, he's actually in the process of trying to cast a spell. You know that Cloud has basically instantaneous spell-casting ability, but you don't know for certain when exactly it is that Sephiroth initiates the command to begin casting a spell, and therefore there is no concrete way of determining how long it takes him between beginning the casting process and actually using the spell. I'm not saying that this is irrefutable proof that his spell-casting abilities are slower, I'm just saying that there's no way to prove otherwise.

Heh, I also have another pretty crippling argument against Sephiroth, but it will take a while to post, and I'm not up for it right this second.