[Matt]

I believe Dr. Carey Mumford teaches that there is no magic number of repetitions per day that will build in a habit. Each person is different and it takes longer with some and shorter with few. He uses his "32-ball drill" to develop habits.

4 balls on manual
4 balls on automatic (with clearkey)

(x 4) = 32 balls

That constitutes a single "unit" of practice. If you're trying to rebuild a habit, it may only take a few 32-ball drills. If it's a new habit, who knows how long it'll take. You just keep at it until your Computer recognizes the new move as what you want it to do and installs it.