I saw a youtube video where the teacher talked about the pick grip you guys are talking about. I can see a definite advantage if you are trying to play speed runs because you have finer control. The only variation I do with my pick grip is to grip it so less pick is sticking out from my hand when I'm doing 16th note strumming patters. The pick will glide over the strings better.

I'm a huge fan of Tortex picks. I just love the way they feel in my hand. I have a skin condition on my hands that acts up sometimes that make my hands less grippy and I sweat a lot. Even in the face of these two things, I can still hang onto these picks.

Up until a year ago, I was using the yellow ones. I've since moved to the green ones (next step up in stiffness). I may try the purple ones one day too. The green ones feel like I have more control.