Do the pros like becker and vai hammer on or pick the high e string if they're sweeping an arpeggio with two notes on it? Is it just preference?
It's mainly preference and sometimes about tone, if you try you can get a real snap off the top note in a sweep by up-picking it and then pulling off when you descend.
R.I.P. My Signature. Lost to us in the great Signature Massacre of 2014.