Exactly. Most actions in idle game mode (i.e. when there's no active battle, micro or macro to be done) are null, the gamers simply repeat random meaningless keystrokes; this helps with being always alert and ready for anything that requires a rapid response.
> this helps with being always alert and ready for anything that requires a rapid response.
I always wondered why they do that, just spam meaningless things like open/close the stats window or click on the background. Some WoW PVPers did it too (like Laintime, I think it was - played a warrior and ran around spamming the character window open/closed an mashing 'weapon swap' even when there was no earthly reason to do so). I figured it was just the result of too much caffeine for 18 hours a day.
This sounds like it's more an equivalent of tennis players' dancing/hopping around, or martial artists doing their ducking/weaving thing?
An AI doesn't need to do this.
Source: Ex pro Starcraft (Brood War) gamer.