I'm currently trying to build up some speed and accuracy in my technique, and I was told a while back that a great way to do this was to play fingering permutations to a metrenome. Has anyone had any experience practicing using this method? Would it be wiser to practice standard scales instead? I can see that permutations are basically just terrible sounding scales, but would learning standard scales offer any advantages? A better understanding in music theory would be a good reason, I think, but if permutations are going to help me more... Any thoughts?
I would recommend you practice with scales. You state a very good point, learning scales is a great way to start off on the music theory path. Using them for practice also provides some benefits;
Learning the notes on the fretboard: Using and learning scales is a great way to familiarise yourself with notes that the frets correspond to. When you know all the notes in a scale, and know how to play that scale, practicing will help you remember which note is which fret.
Improvising: When you know the key signature of a song, using that scale is a great way to find the notes that sound best in a solo.
Speed Practice: Learning to play scales quickly (but not rushing) is good, because you will begin to learn your way around the neck and be able to play quickly and smoothly without any accidentally muted or buzzing notes.
Hope this helps.
There are two kinds of fast: Ripping through scales and Playing the notes quickly - what does that mean? Playing a scale fast is not always playing music, but just having the muscle memory to move your fingers and wrist quickly over a pattern that you've practiced over/over/over. If that is the kind of speed you want to build up, cool - it sounds good, feels good, and will probably get you laid - just keep practicing the scales over and over and take time each day to just see how fast you can play through them for 15-20 minutes. Think of how runners do those quick sprints before running the 100 yard dash - you are just training your muscles to go a little faster each day and eventually you will break through different speed barriers if you keep pushing.
If you want to play fast, accurate notes that are a little more mindful of each individual note - learn melodies that aren't guitar melodies: Sax and Trumpet are a good start. Take a slow solo from Miles Davis, Tom Scott (Tom Cat w/robben ford) and learn it. You will be surprised how your accuracy and speed will build because you are breaking out of your comfort zone, muscle memory wise. Listen to Herb Ellis, Early George Benson (Prodigal Son) to get a good idea of what "fast" is, that doesn't really sound fast until you try to play it....
You should be practicing it all. Small scale fragments, motives, scales, chords, etc! Everything! Do you wanna only play fast scales? Or do you wanna make music?