[bunderbunder]

It isn't for a great many tasks. Basically, whenever you're computing f(g(x)), you can't execute f and g concurrently.

What you can do is run g and h currently in something that looks like f(g(), h()). And you can vectorize.

A lot of early multiprocessor computers only gave you that last option. They had a special mode where you'd send exactly the same instructions to all of the CPUs, and the CPUs would be mapped to different memory. So in many respects it was more like a primitive version of SSE instructions than it is to what modern multiprocessor computers do.