If you want proof that TA works all you have to do is read through volpri's journal. He analyzes his trades and shows exactly how he trades. He made one response on this thread but is too modest to promote himself. He is a day trade scalper and does it brilliantly.
I especially like his ability to realize when he is wrong and exit right away and double up in the opposite direction. He showed a very good chart a while back where he had to do this twice in that even his doubled up position was in fact wrong and he did it again in order to get back on the correct side.