Sampras did not have the same gaping quality differential over his peers that Federer does. (In Fed's case, substitute 'colleagues' for the term 'peers.')
Pete, for all his greatness, racked on average about 1+ Slam a year over a 13-year period (1990-2002). That's great. In fact, when Pete really hit his stride in 1993, he proceeded to win 13 Slams over 10 years (1993-2002). That's really great, but you can't say that Pete was an absolute lock to win any given match, except at Wimbledon. Pete had, you know, 'human' traits that made him lose the occasional contest.
Fed's probably the greater player, but I've got to believe, as others have said, that Fed's playing in a softer, less competitive era, and that it's not just that he's so bloody brilliant and that's it. Most male pros of quality these days play a power baseline game and rarely volley (no, I don't count as 'volleying' putting away dead ducks at net that you've caused because of your powerhouse forehand). These guys have big serves, big forehands, big everything - and tiny, essentially non-existent options when it comes to beating Fed. Sorry, but that's boring.
Fed's got his method down cold. In some ways, he reminds me of that guy who studied up on the 6 or so patterns that were used on the 'Press Your Luck' game show board, got on the show, and fleeced the network for over 100 large. The other top male pros these days have about just that many (6 or so) ways to win a match, and Fed's figured out how to eradicate those ways. Uh, 'Golden Era' of men's tennis, this ain't.
Thanks. Oh yeah, to add my 2 cents. Federer has just as good competition if not better. Sampras was never as good as Fed, never. Therefore the rest of the pack was closer to him appearing as if he had tougher competition. But not so tough against a player of Fed's caliber. Remember a Nadal fan is saying that.
