As @Frylock points out, we’re talking about two very different things here. There’s motor learning aspect, and athletic training. Motor learning is what you do when you learn to ride a bike, surf, or draw. Nobody bursts / drills those activities using weightlifting style techniques. They’re all about teaching yourself to do a complicated movement in a natural way, make it accurate, and then make it permanent. In that order.
Burst-style training is for athletic development in physical speed or endurance, like what @milehighshred did to train for the speed contests.
As it turns out, @milehighshred is actually a bit of an expert in both. As he explains above, he did a wide variety of things when he was learning, on the one hand metronomic and speed oriented, and also lots of other stuff, from playing covers to writing riffs and songs. His current technique is the result of this mix of approaches.
For example, when you look at things like John’s finger-oriented crosspicking technique, that’s not something he planned out methodically. And it did not come from high-speed bursting with a metronome, because this is a technique John uses at medium speeds, not fast ones. It came from randomized practice and experimentation. When you hear players talk about sitting on the couch and tuning out to the TV, this is what they’re talking about. Eddie Van Halen tells that story as do lots of players, as you mention. They’re talking about the bike riding / ball throwing motor learning. They are trying to encourage this by letting the hands find natural movements on their own. If you don’t actually know what hand movements you’re trying to encourage, and you’re operating in complete ignorance at random, the hit rate is going to be a little low for this. Which is probably why a lot of players are confused about what this type of practice is supposed to accomplish.
So! Here’s the bottom line:
Whenever we talk about practice, what we need to do is be super clear about whether we are referring to motor learning or athletic training. Just ask yourself:
- Q: Is there some complicated hand movement you’re trying to learn how to “do right”, like riding a bike?
- A: That’s motor learning.
Or:
- Q: Are you trying to increase your raw physical capability?
- A: That’s athletic training.
Yes, of course they overlap. You can’t get super fast if you’re doing the movement wrong. But until we learn to separate these two fundamental activities when we talk about “practice”, we’re going to be talking in circles around each other.