Why is Fire Punch the main slash on the DD set? I'd assume you'd only try sweeping with TTar once Ferro is removed, anyway. Crunch + SEdge + IPunch is so valuable, really, that I can't image the mains being anything but those. Crunch and SEdge just hit hard and IPunch is usually the only coverage late game you'll need. (Altho Superpower is probably good, too, but Fire Punch is overall mediocre.)
And I'm sure Crunch / SEdge check Ferro / Skarm respectively, too?
EDIT: Choice Band is neat. Can confirm it's greatness. But I'd simply slash it on Scarf and call it "Choiced" Tyranitar, or put Band in the OO mentioning, since the moves are identical on the sets. (OO seems best - you can even slap in alternative EV spread for it in there since you can run more bulk since the speed isn't as important.)
Also, haven't checked, but Scarf Tar should be: Crunch, Pursuit, Stone Edge, Superpower. Superpower and Pursuit are so important; traps are amazing right now, and Superpower can pick off so many threats it isn't even funny.