What they should have done instead of Combot is have a Training mode ala Street Fighter 4, complete with combos, wall combos, bounds, punishers, tag techniques and tag combos.. for every character.
It should have also included trap escape techniques.
This way you'd actually be able to learn the clutch stuff.
The reason I suck at this is not what everyone wanted to dog me on many pages back. It's not enough to know a couple characters. You basically have to at least have a basic working knowledge of the entire roster (which I do, I'd say I know enough to get by with at least 20 characters in a non tag Tekken, and know about 4 pretty well, not pro standards but I really remember a lot of moves and strategies), and also you have to seriously practice not just regular combos but wall combos and tag combos for anyone you intend on using.
The tag system and wall combos are unskippable elements to this game, unlike say, earlier Tekkens or Street Fighter where a little strategy could go a long way. You cannot survive in TTT2 without knowing the advanced stuff, if your opponent has a good handle on it, no matter how well you know the rest. They're not an extension of the game, they're a core part of it, and there's no way around it if your opponent has a grip on it.
It's extremely overwhelming if you haven't followed the series from day 1 and I agree with all those above who say Tekken, at this point, has become the hardest 3d fighter, from scratch, to get into.