The difficulty in this game gives enemies more hit points and make them hit you harder or that could be in reverse.
Not sure why people get offended by what difficulty they play on, I play adept and I might go expert again and see how it is for a long course of play.

Being my character a stealth lvl 53 one, i HAVE to play on master. I wouldn't mind having an harder option tho. Yes, stealth is overpowered.
Ah btw, I started the game on expert and turned to master once I realized my perks were making it too easy. Never had to go beyond expert.