Read, read, and then read some more....I find the best way to improve technique is to do alot of reading and don't look at your hands. This requires you to "feel" the piano and play into the keybed. I have many friends who are Jazz players who's technique is severely deficient and they are poor readers. I think there is a direct correlation here. The more repetoire I get through in the 4 major periods (baroque, classical, romantic, 20thc.), the easier I find passages that may have been difficult a year or 2 ago. The technique sort of takes care of itself when you focus on listening to the "sound" your producing rather than looking at the notes your hitting.