In all my prior experiences playing and watching organized basketball, the only consistent use of the underhand backdoor pass(picture someone bowling a basketball) is by the De La Salle high school spartans of Concord California.

De La Salle is most famous for their football(consistently ranked top 10 in the country) their basketball is no slouch either but I've honestly never seen something so bizarre yet works so well.

My school plays annual scrimmages with DLS and their freshman JV and Varsity(to an extent) all rely on the underhand backdoor as a main part of their offense.

I know people try this much more in pickup/streetball or even some unorganized AAU/Club teams but have you guys seen underhand passes or other crazy styles of olay in an organized setting(high school, college, etc)?