um.... never mind all the rest. you got a crucial detail mixed up. revan came first. bane learns the thought bomb and and force drain and many other force abilities from REVAN. specifically his holocron. bane reshaped the sith order and instituted the rule of two after learning from REVAN. ergo, you cant have bane, at least they way we know him, without REVAN.
and to make bane canon (not cannon lolz) with the history we know of intact, the thought bomb, the rule of two, all that.... to do that means revan has to be made canon. which means, yes KOTOR has to be made canon. In regards to revan, which means a lot of KOTOR becomes canon because revan is a critical part of KOTOR.
