Some people's idea of improvement is un-realistic. You improve rapidly when you begin, because basically you don't know squat and you can get the basics down pretty quickly and drastically improve your scores. Then the work begins. The better you get the harder it is to improve. We are talking fractions of a second at a time so those improvements are hard earned. Whether you shoot open or limited or both, I don't think it really matters, the time spent practicing properly with either is what will determine your progress. Look how long TGO has been shooting, and he improves with time tiny fractions at a time and I've heard he still practices My 2-cents