Since I've heard a lot of people (RL friends especially, though some on these boards) wonder why both Sith and Jedi use their force powers so sparingly when they could be pulling and pushing left and right.
Well, there is an answer. This 'Superman Dilemma' has been a major topic of discussion in some places when issues like this arise. When a writer gives a hero or villian extreme superhuman powers (the force, for example), we arrive at the dilemma.
Given these powers, and their logical use, there would be no storyline because the powers are just ridiculous (example, superman has SUPER strength and can fly at light speed right? so why doesnt he just kill all the villians at the speed of light!, or why didn't the Jedi just force push all the battle droids into oblivion, etc. etc.) so something has to be done. There are 3 (really more like 2 options). One, which GL did with another option, is to make a moral code prohibiting tons of use (Jedi code sort of thing). While this sometimes works, it certainly doenst for antagonists and it still is only a short-term fix.
So the writer arrives at two possibilities if he or she is to put meaning into the story.
A) In almost every story, creates something that will make the hero unable to use his force powers (ala superman)
B) For no apparent reason, the heroes and antagonists use the force powers sparringly.
As anyone can see they're both sort of...stupid, but in most people's opinions, B is superior.
This is common sense to some of course, but I thought I'd point this out to those who dont see any reason why the Sith dont just run into a room and just lightning everything