Hum, isn't cilk-like work stealing depth first? Idle executors steal oldest ancestor and busy executors eagerly execute recursive calls while pushing parent in the local job stack?

Proof of optimality was in the early cilk papers in the '90s.

I'm sure the same algorithms made into Julia via Intel (which bought cilk in the early '00), but it is hardly new except in the 'everything old is new again'.

Also IIRC OpenMP supports (or at least allows) work stealing although at least GCC does not implement it yet.