I've searched the forum, and there seems to be very little discussion of ABSIV's (Armistead Burwell Smith IV, aka Zach Smith) technique. He's utterly fascinating to watch. In this recent clip, he's doing a bunch of his usual tricks, arpeggiating and strumming chords, and something I haven't seen before - fretting a note on his G string with his right index finger while plucking the string with a flick of his right ring finger, to add a high note while continuing to play the other strings farther down the neck and picking them with his right thumb. I've seen people add right-handed tapping to achieve a similar effect, but never saw someone multitask fretting with a right-hand index finger, plucking the high note with their ring finger, and hitting the low notes with their thumb simultaneously. Far from gimmicky, it lets him hit notes that are far enough apart that they'd otherwise be unachievable on a 4-string. He's a mastery of 4-string polyphony. And the track is sweet too, of course.