It is more difficult to photograph one's right hand than one would expect. Especially when one is right handed. :p

I used the brightest coloured pick I had. Here is my "normal" position in playing mode:


The result of this position is it changes the angle of the pick making it other than a straight on 90 degree attack. (I have seen picks designed to make this happen.) The hand is closed into a fistlike position which seems to reduce any extraneous movement and keeps the pick in very tight control. And the flat angle of the thumb & index acts kind of like a combination depth gauge and mute mechanism.

I also remembered seeing a G-Dec demo with the dude from Def Leppard. I watched him deliberately take the same grip just before running a little riff.