For some of you gear heads out there, ever notice how crappy an engine runs if the timing isn't correct? If it's off a few degrees, it will either belch a fireball out of the carb, or will simply crank and do nothing.
In an effort to make my guitar playing better, i decided to dust off the met when i play scales. I start with a pathetically slow 1/4 note beat @ 40 BPM, play the scale 5 times thru, and increase the BPM by 10, and play it again 5 times thru and so forth. If i stumble on a note, (this counts note clarity and timing) i start the process over until i get it correct. I had better be playing the note on the click of the met. All this repitition has trained my brain for proper timing perception, and i'm committing the scale to memory. I like to play box scales string to string versus the single string scales, although single string scales are a good finger stretch excercise. Also, i try to either look at the met or the scale tab while playing, in an effort to get used to looking around while i play, so i'm not isolating myself in a bubble. The more i repeat it, i'm finding it easier to not be staring at my fretting hand so much when i play. At one point, at 70 BPM, i was able to look up, and watch something on the Military Channel while i was playing (hey, they were talking about one of my favorite WW2 fighters, the P-38 Lightning)
While not as glamorous as learning an Eagles tune, it does help with the fundamentals of guitar playing, timing and scales.