That would be very similar to Objective C's asynchronous blocks. The system manages a queue of blocks and a set of threads to schedule those blocks in. I think

That would be very similar to Objective C's asynchronous blocks. The system manages a queue of blocks and a set of threads to schedule those blocks in. I think (and I recognize I'm not a theorist) that the synchronous aspect of the queue management is still going to hurt for the original "add numbers in a loop" case until we get better hardware support for them. Is it better than spawning a thread? Of course. But it still isn't ideal.