I have had a single experience, that I remember, where I did something in a dream and it helped improve my RL skill. I was not lucid at the time.
I was on a soccer team in High School, and I couldn't take long distance shots well. But in my dream, I took them over and over from outside the 18'. Well, the next day at practice, I took a few shots from where I had in my dream, and I was placing them at the top of the net, just under the goal post. It felt pretty amazing.