You're experiencing a common phenomenon in skills training: The "plateau". The fact is that the perceived time with no progress is an illusion. During the time you are not speeding up or not getting more accurate you are in the process of learning things that just aren't getting integrated yet. When they are integrated, that's the time things just seem to fall into place; you get a spurt of improvement, and then you get another plateau.A great suggestion is that you tape record yourself periodically. You may not see much progress, but give it three or six months, and you listen to those earlier recordings, you'll be impressed at the progress that happened.
Dave Oesterreich