New Orleans has a rich history of one-man bands. But the ante has been upped considerably by transplant Dave Gregg — or, more to the point, by Gregg’s toes. Gregg can be found weekends along the river or on Royal Street, playing one guitar with his right hand, another guitar with his left hand behind his back, and the bass guitar with his bare feet.

“It developed out of a flashy ’80s guitar techn...