[jberryman]

> My experience is limited, but a generalization like "always going to be easier" seems rather at odds with reality.

You're probably better at reasoning about nondeterminism than I am. In my also limited experience, even trivial parallel algorithms are tricky to get right. So it seems to follow that an algorithm that took more thought (say, something using speculative parallelism) would likewise be even trickier to implement correctly.