Ok, once upon a time I did a stint playing bass and guitar for a group that did gaelic folk music and various other folk styles. One night after a few hours of rehearsal where i pretty much played nothing but a slow steady “bum, bum” on the bass, I went home and picked up a guitar to play some classical guitar. My right hand was so loose and fluent I was surprised. All that slow playing had made me fast.
As time went on I began a different style of practicing. Instead of charging into it like a ram in heat I’d start out with my morning coffee, occasionally taking sips while playing at a rate of about 1 note a second to 1 note every few seconds. After maybe a half hour I’d do my regular practice routine. I found this served another purpose I hadn’t expected, for which I try to get my students to follow this method as well. Playing at such a slow relaxed pace every time I picked up the guitar had served as a sort of self-hypnosis, I think. Whenever I picked up the guitar it would have such a relaxing, cathartic effect and my muscles would become relaxed and ready to play.
Like wild Bill Hickock said, “take your time in a hurry.” Playing slow can actually increase your speed as well – it’ll give you time to hear what’s going wrong in between the notes, which is where you’re most likely to lose speed. And then again there’s what i call “infinite speed” – being in 2 places at once. Can’t get any faster than that. But maybe that’s a discussion for another time.