Well, I could make a list, but it'd end up being about the same thing as most are coming up with... however, I do have a few thoughts on this subject:
* Dez is strong. Not weight room strong (although he probably is), but country strong. He is just a really strong guy. Even coming into the league, he was one of the strongest WR's in the game. I still remember Dez in his first professional game ever (which was against the Commanders), catching a little smoke route behind the line of scrimmage and when the DB got to him, Dez literally grabbed the guy, swung him over his head and down to the ground. It was one of the finest examples of strength from a receiver that I'd ever seen That was as a fresh faced rookie in his first game. I knew right then that we had something special. Heck, you can tell from how difficult he is to tackle that he is just a strong man.
* Speed is relative to the position. In other words, there are hundreds of guys in the NFL that run faster than Tyron Smith but I seriously doubt many of them play on the offensive line. Smith is damn fast for an offensive lineman.
* When I think of speed in relation to football, I typically think more of lateral agility and change of direction just as much as straight line speed. At most positions in football, the first step quickness and change of direction is really more important than their time in the 40 (straight line speed).
* On the DL, quick get off is much more important than their 40 time.
* At LB, change of direction is just as important as how quickly they can get to the sideline.
* A relatively slow WR who doesn't have to decelerate much to make a cut will usually have just as much separation as a guy with sprinter's speed.
* Football speed can vary wildly from the 40 times guys have at the combine and their pro days. We've all seen guys who simply don't play as fast as their time says they should... just like we've all seen guys who play a whole lot faster than they timed. Dez Bryant is one guy who runs in pads a lot faster than his 40 time says he should. You almost never see Dez get caught from behind and when he does, it is just barely. He also is so strong in his lower body that he accelerates instantly and changes direction while losing almost no speed. Dez is the epitome of a football player, not a track guy. Terrence Williams is another guy with football speed that is far beyond his times speed. Both WR's are fast but not blindingly fast... but they both have tremendous football speed in pads. I wouldn't trade that combo of 1 and 2 WR for any other combo in the league.
* As far as smart goes... I think that, in relation to football, instincts are a lot more important. I do think that flat-out intelligence is important to, but understanding is more vital. A knack if you will. An inherent knowledge of angles, leverage, finding the open lanes, and timing. An ability think fast. To react in a manner consistent with winning your battle. Guys like Randy Moss and Dez are pretty tall but that height doesn't account for their uncanny ability to high-point the ball and get it before the other guy does. That is just something they were born with. You can coach it to some extent, but really you either have it or you don't. So while I do think intelligence is nice to have... it is a player's innate understanding of his position that takes him from good to great. Emmitt understood angles, leverage, and momentum better than just about anyone else. Emmitt would never be mistaken for a rocket scientist, but you won't find a more football savvy guy in the NFL. Coincidentally, Emmitt was another guy who timed poorly but almost never got caught from behind. His leg strength allowed him to have a rare change of direction and his vision (i.e. football smarts) allowed him to see the open spots, and his strength allowed him to break the tackles of the guys who were lucky enough to actually get a hand on him.