Coach Kevin Kelley of Little Rock’s Pulaski Academy can tell you. His team also almost always uses an onside kick, too.
Turns out, there’s a good reason to reconsider the automatic 4th down punt. And maybe the mechanics of kicksoffs, too. Kelley’s done very, very well with his unorthodox approach, and has some data backing him up.
(This reminds me of the New Yorker story about the girls’ basketball team that always did a full court press, which was (of course) written by Malcolm Gladwell. The girls’ success was ended not by spectacular tactics, but by a ref who decided he didn’t like the clearly legal approach, and started penalizing them; obviously, this isn’t happening to Kelley.)