GlaDOS totally makes the game.
"If at first you don't succeed, you fail."
"Do not touch the operational end of the Device. Do not look into the operational end of the Device. Do not immerse the Device in liquid, even partially. Most important, don't ever, ever, ever.....{garbled}"
"Failure will result in an 'unsatisfactory' mark on your permanent test record, followed by death."
I have found Steam to be unobtrusive and in general not a problem, but I haven't tried to reinstall anything yet. I even got Portal over the net with Steam.