One of the most satisfying things for me is when I actually execute a strategy or concept that I've studied and watch it succeed in real live play. For example, I had been studying a lot about short stack play and the importance of "re-stealing" the blinds when your stack is getting short. Shortly afterwards, I played in a tournament where the player a couple of spots to my right was raising in LP a little too often. It was quite successful for him, but he was ignoring the fact that my stack and the stack of the guy to my left were getting close to the perfect re-stealing size. Over the next several orbits, we re-stole his raises probably 5-6 times and I went on to cash in that tournament. No matter how much you read/study concepts, nothing beats actually experiencing them in real poker play.