The idea that Subtlety isn’t “viable” for raiding is false.
I had an entire thread on the old forums detailing this along with parses (which are no longer available due to the new parse site).
It’s absolutely viable as long as your guild isn’t anal about debuffs, but hemo can absolutely be a game changer if your raid is melee-heavy, and at the very least competitive with a corruption if all stacks get consistently used.
I’d wait for the 16 debuff cap on K3 if you’re playing there, though. If you have any questions about playing Subtlety just ask. I could reliably keep up with combat rogues in my raid sporting CTS’s, Maladaths, and DFTs. It takes some finesse but it’s really not difficult, and the perception that it is a blatantly inferior spec is flat out incorrect. Especially later on when you can pick up the servo hammers from Naxx.