I wrote up a post on my blog (first post ever, actually) that describes a variation on RTS gameplay that I've been told I should post here. The article is at http://www.not3d.com/wordpress/?p=3. Comments/criticism/kudos welcome.

I think this kind of Macro-Management has been adressed somewhere before. I do think people enjoy micromanaging their troops, if only to ensure their strategy goes as intended. The problem with doing high level strategies and by-passing the micromanagement is that the success of your overall strategy can depend on the quality of the games AI, that kind of lack of control can be disconcerting to some people since they don't have anyway of knowing if their strategy was valid or not because they weren't in on the micro-management side of it.

I do think it can work though if you designed a good enough AI and gave the player the ability to overview the events that are unfolding (so he can see if the strategies he implements go as planned, or if he needs to rethink his approach).

You may also want to look at Savage, which is an interesting FPS/RTS game, where you can play as a RTS commander, or run around as a "unit" in the field, taking orders from a commander. This sort of gameplay i think naturally blends well with your idea, since one player can give an overall strategy to a group of FPS players, they go and and figure out the rest themselves while the RTS player keeps an eye on the overall campaign.