From what I gather, he's playing much the same way as MAB does, as far as picking angle.

He got fast the way everyone back then became fast in their own style: Practice and then some more practice, just driven by the thought of being fast.

Nowadays, everyone copies the style of the latest fast player, with hopes to reach the same speed instantly, but that's another story.
From the look of the solo he uses alot of legato, that being you pick once and use hammer-ons with your other fingers. Also, when he is actually picking some of those fast runs his hand barely moves, he keeps it very tight to the strings.
yeah hes a heavy legato user, but his picking style is awesome very pointed,tight, and calm.