I thought I'd ask here if anyone has any thoughts about a certain technique that I've seen at the further edges of the repertoire.
it's basically two independent continuous lines, and is played either:
p- i- p- i
p- i- p- i
It seems Yamashita uses the former in his big transcriptions, and the latter is found regularly in Eötvös' transcription of the Goldberg. I've also seen people use it to play the Bach Prelude BWV 847 (although Sanchez fingers his transcription with the thumb doing all of the bass). It also seems like it is well suited for use in pieces that have Alberti bass.
Now in theory, what it does is remove the speed limit imposed by having to use the thumb only for the bass melody. So instead of being limited to how fast one can play p-p-p-p, ideally it's now how fast one can play p-i-p-i or m-a-m-a. (or, perhaps, as fast one can play double-trills on the piano). However I've practised it a little bit, and have noted some issues:
poise – say you're playing on 1 & 6 - should a & m be rest strokes so that i can get a good swing at the 6 string?
stretch - if you're doing the version starting with a then the cross-string stretch between i & m when they play together can be uncomfortable.
tone - p-i-p-i isn't great for legato
also, string crossing is not always ideal, especially going from m on 1 to a on 2 or that kind of thing: if the notes are continuous and fast you're kind of 'locked in' until the 16ths stop!
But anyway, the question is: does anyone use this technique regularly? Does it appear in more conventional repertoire and I've just not noticed it? Does anyone recommend it or is it not worth thinking about?