No way, Sampras of 99 was better than the 93 to 95 Sampras in my opinion. Sampras' was cat-like quick back then, not nearly as bulked up, must lighter on his feet, just all-around faster. The older Sampras lumbered around the court more, in my opinion.
The younger Sampras had better groundies, his forehand was still dangerous; but the big difference was that he hadn't lost the confidence in his backhand yet. It was a much more consistent stroke back then and it's true he did not slice nearly as much, which is an indication of lazy feet in my opinion. On the serve, Sampras' always been great. Volleys, Sampras...Federer can be very inconsistent at the net, and I've never really seen him live and die at the net and prove that he was good enough to win by just that way alone. As a mix-up play sure, but I don't see how he's any if at all better than Pioline in that regard. To me, Federer's Pioline with a more cunning AND powerful forehand, a worse backhand, and a better serve...plus, FAR more consistency from match to match, and without the tendency to choke in the finals.
I see the comparisons to Sampras, but I think game wise, Federer's more similar to Pioline except that he can go for the knockout punch on the forehand that Pioline couldn't. Pioline's forehand was very good, but what he lacked was the killer inside-out forehand. His technique was too old school and rigid for that in my opinion. A slightly more modern, semi-western slashing style forehand technique might have taken Pioline to the next level.
But if you look at the BRILLIANT all-court tennis Pioline put together at the 97 Wimbledon semis, that is the Federer I see day in and day out that we never saw in Pioline.
Sampras played a slightly different style in my opinion. Federer's got more flexibility on his forehand from the deuce court. He can flick angle a lot better than Sampras. Sampras' forehand was more rigid and predictable by far from the deuce court. It was built around a running forehand that he could smack for a FLAT winner either down the line or crosscourt. You knew what to expect, you just had to brace for it. On the ad side, Federer clearly has the better inside-out forehand, no comparison; it's just a hair less powerful and devastating than the Moya and Roddick's of the world in my opinion. His inside-in forehand, I'd give the edge to Sampras as Sampras struck a cleaner, purer, flatter ball which is always beneficial when going down the line. Overall, I'd say they were equal on the forehand. Sampras' was a more straight forward bludgeon the ball for a winner, brute force, knock you on your heels type forehand. Federer a far more versatile forehand that's is neither overspun or underspun. On a good day, Sampras' forehand is better...similar to how Petr Korda's backhand was an impossible force to face *when* on. BUT, if facing a net rusher, I'd cleanly take Federer's forehand on any day. Federer would give a net rusher less rhythm and so many different looks, angles, speeds, and spins to deal with and react to. He would make them look far sillier, in my opinion.
As far as movement goes, Sampras was every bit the athlete and as fast as Federer in his prime, but Federer gets the edge because Federer takes more pride in his movement slash scrambling ability in my opinion. Sampras could loaf around sometimes, go on cruise control, knowing that one break was enough...he conserved himself mentally this way, and I think this is why he lasted for so long.
But if both were going all out against each other in a one match only setting in a final, no doubt Sampras would hold his own in the movement department.
As far as backhands, early in his career, I would say Sampras was equal to Federer on the backhand. Sampras' biggest flat backhand was bigger than Federer's, similar to his forehand. It was a laser-beam type shot, struck very flat. In terms of slice, Federer's better, he tries to knife the ball a lot more. Sampras, often got lazy on the slice and didn't go after it too agressively. In terms of passing shots, Federer's better. He sets up and prepares much more compactly. On a confident day, I take Sampras' backhand, on every other day Federer's. Overall though, I think Federer's backhand is vastly overrated. No way is it comparable to Pioline (like he was born to hit the shot, so comfortable hitting it under any conditions) or Kuerten (blazing angles) or Korda's (flat stun gun of a shot) or even Muster's backhand (unbelievable topspin/visciousness and absolutely relentless and machine like, never missed) at its best.
As far as approach shots, they're even. Both get in unbelievably quick.
As far as overheads, Sampras no question...because he did the cool leaping thing for oohs and ahs points...but it doesn't really matter though since name one pro who can't put an overhead away in his sleep? Yeah, that's right. Overheads are second nature for all pros, and besides they are very seldom forced to hit them anyway, and usually at the pro level, the overhead is ALWAYS a gimme, except for the very occasional PERFECT topspin lob that occurs NEVER more than two or three times a match at the absolute most 99% of the time. And on a perfect topspin lob, it wouldn't matter if you were Michael Jordon, there is no answer. It's just one of those shots you accept, and move on.
As far as returns, Federer because he tried on the return more consistently. Sampras just bid his time, he wouldn't really go all out on the return but once or twice a set in order to get that one break. When he did try though, certainly he had very little problems to break when he actually needed it. In order to summon the key break at will, you actually have to be able to have the ability to break at will. Sampras had that ability, he just chose not to try and break every time. If Sampras tried more often on the return, they would be equal in my opinion.
On serving and volleying, no question Sampras. Better serve with both more spin and pace (I'm not buying the *clearly* inflated service readings these days...come on, no way Grosjean can serve 125 out wide with the same service motion in the mid 90s). Think about it, Federer and Sampras have pretty much the same build, and the same racket, and a similar motion...the only difference is that, Sampras' motion is a more advanced one, a more difficult one, and a more rewarding one if you think logically. Much deeper knee bend, buch better shoulder turn, much better shoulder tilt, etc. There is NO WAY that Federer is a harder server or serves with more spin than Sampras' unless you take into account the new style radar guns which record the speed of the ball much sooner after leaving the racket than they used to.
On the volley, Sampras is better, no doubt. Federer can be a flashy volleyer, but he's not a consistent volleyer. The illusion of his greatness at net is just that an illusion. I've never seen him live and die at the net like Henman and Rafter. Let's see him serve and volley his way to the semifinals or finals of the French Open like Rafter and Edberg did, and then I'll be a believer. Federer volleys in spurts, he's a pretty boy at net, but there isn't the substance...of a Sampras caliber volley. Meaning, Sampras can live and die at the net with anyone. His volleys are that solid, that consistent...plus he can go to the drop volley too. Mechanically, Sampras was more precise at net, more surgical, and more intense, and far less sloppy. Oddly enough, it's the exact opposite from the baseline where Sampras is the one who is less refined and Federer the one with the far more precise footwork.
Overall, it's a pretty even battle here.
On faster courts and particularly indoors where there are fewer elements to deal with, Sampras wins 5 and 5. On medium hard courts, it's anyone's game, likely tie-breaks. On clay, Federer wins 3 and 3, sometimes 1 and 1, haha...Sampras was too stubborn on clay, always tried to stick it at the baseline even though his flatter groundstroking style wasn't suited to the dirt.