It's actually the other way around, I'd say. Individual unit control follows very naturally when you have unlimited APM. And most of the time you can define simple and good criteria on how to position the units (e.g. concave, or exactly the right distance apart to avoid splash damage, or one unit a tiny bit more towards the enemy to be the first one targeted by incoming fire, ...). Build orders can be programmed, yes, but transitioning between strategies properly based on observations and guessing or judging the enemy's strategy is quite hard.

The ones I saw in the competitions lost against humans on such micro rules since the humans quickly intuited their blind spots. The ability to bluff and screw with AI's, a human strong point, is what made me predict Starcraft was going to be way harder than Go. I'm still betting on the human in this one.

And the last line you said is also true to make things even more difficult. :)