Until earlier today, I had completely forgot about this little technique Satch has used a couple of times. Mostly notably in the beginning of the Surfing solo and in a section in Raspberry Delta Jam V. I’m sure he’s used it once or twice in later albums but I’m not as familiar with those. Here’s my crappy version of those 2:
I’m not too sure what it would be considered, but it does seem like it’s similar to one of the tapping tests. It’s a bit of a cheat for that since you’re using the string to bounce off of, sort of like a drumstick bouncing off of a head. It’s probably not usable in any other picking context but as an exercise, perhaps it can help with wrist strengthening and/or endurance? I do notice that since I hadn’t done it in… 20 years, that part of me wants to pick it in a regular motion, which itself has a pretty cool texture. Kind of like EJ’s Koto thing…
Either way, it’s a fun thing to do, lol