Yes, Mark, Pete does use a straightened pick on his middle finger to frail and uppick which he wears backwards. This is true.

When you wear picks, using the ring finger is cumbersome on fast tunes. What Pete used
to do was to wear straightened picks on both his middle and ring and he could uppick with these on backwards. I haven't seen anyone else able to do this effectively.

Erik Darling always used curved picks on his first and second finger and frailed with his ring finger.

I find the plastic picks harder to use. These are the new ones, I forget, Kelly or someone.
They are clear plastic. The best sound is either metal or no picks at all in my opinion but
everyone has a sound they like the best.

I have a Lucite resonator on my RB175 long-neck that gets a good volume without picks at all.

Frank