I will say this. I considered superbouncing cheating. Even though technically, yes, it was in the game and everyone had the ability to do it, whoever did it first, had a huge advantage. I can see the argument for the BxR/BxB. But the Doubleshot, as Carts said, took an insane amount of skill. Timing the doubleshot properly and aiming took a lot skill. Plus, the big disadvantage was, if you messed up your Y+Y switch, you were probably gonna die. Besides, if you were dumb enough to run in a straight line the whole game, you deserved to be Doubleshot.
And Destroyaaa said, I never did superbounce in MM but I did customs just have fun or get out of the map. I spent hours upon hours doing that. I actually did something in Halo 2 that I never saw anyone else do. I combined the BxR with a Doubleshot. B-XR-RX-Y-Y-R-RX. I took me forever to get it right. But it was a lot of fun when I finally did.