My practice time is very limited nowadays (1-2hrs/day)... so I'm creating a practice routine to maximize my time. My question is specifically about this philosophy:
"Don't practice what you know, practice what you don't know"
In the structure of a formal practice routine, how does one differentiate between learning/memorizing something and perfecting it? When I'm perfecting something, I feel a little guilty--like I'm playing something I already know... over and over. Here's a specific example:
Let's say I have the goal of learning a certain sweep arpeggio shape. After just a few practice sessions I've got it down cold. I've memorized the shape and can play it pretty well. However, I continue to play that arpeggio over and over, in all keys, at nearly every practice session. I do this because I'm trying to perfect it, and get it clean and fairly flawless.
However, aren't I just "practicing what I already know"? How do you perfect something, if you're constantly moving on to new stuff? I'm sure I'm misinterpreting the "practice what you don't know" philosophy somehow.
The more comfortable you get with the arpeggio, the less time you need to spend practicing it. Therefore you could spend the first 30 minutes or so of your practice routine applying all the ideas you have been working on, to a backing track.
You never need to spend 1-2 hours on 1 exercise/lick, move on to harder exercises.