>OK I'll look at the BatchingExecutor. The iteratee library sits outside Play core and doesn't have a dependency on Akka, so it's not something we can use easily without reshuffling our dependencies.

Ah, that's a shame.

>Can you expand on your "consequences are many" comment?

You risk messing up someone elses Thread, unless you are _extremely_ careful with how you use same-thread execution.
No user-callbacks / functions should be executed on that sameThread for that reason.

Being scoped to play is just one thing, every use case needs to be deliberate and thought through. I had to spend a lot of effort securing the Future impl.

Does that help?