I have found, playing the demo again, and again, and again (waiting for 19th... sigh), I have found that each time I used the kata moves, the efficiency was close to zero... since you can't move or your move are programmed and you can only turn, jedi enemies just back away and for for it to finish...

Only 2 cases where I found a kata useful :
-surrounded with regular (non-jedi) enemies
-the light stance kata, since you can freely move while performing it. Can wreak havoc on jedi enemies....

ebelleudy

Only the red stance and only when its safe to use it.
I like it because its relative short (not like the yellow) and is good when someone attacs you with a DFA, that yellow JO special, the 2 saber throw or any othe move that leaves you with 0 defense. Then hit him with a red Kata when they are defenseless(only the last slash hit, the twirls are just there to make it seems cool).

The bad is that requieres a really dumb oponent (AI mostly) that starts doing useless moves that looks cool, but even if it wors once every 100 fights it the one I use most.

Blue is nice against non saber wielding oponents.

I don't like yellow kata, but overall is my fav stance.

I have found them to be pretty useful, especially when your opponant is turning on rage, finishing a move, and so forth.