[BRPORSCHE]

WI,
This is a tough question. The answer isn't as straight cut as I want it to be, but I'll try to be as clear as possible. The lower Center of Gravity definitely plays a role. Corners and saftey's are constantly changing direction, reacting to what the WR is doing. They are running a sub 4.5 at the corner. Now, the corner is running a sub 4.5 backwards for the first ten yards before they can turn their hips and chase. It's that split second reaction time that makes them that seperates the so-so collegiate from the pro.

I was reading on ESPN this week that their are very few top defensive backfield positions. You can drop a DE to be an outside LB, or possibly even a nickel back. Now that DE will still be a very productive LB, since you only moved his position back 3-4 yards. Now to make him a nickel requires a lot of skill. The tall lanky DE's never get picked. It's always the slightly smaller and more agile ones. They have to be able to take a hit, and be able to accurately place a hit in open field. Thats where the low CG comes into play. These guys have to turn on a dime.

This still doesn't answer your question about the WR's though. I was never one, never had the hands for it. Look up LaRon Landry. I personally think he is the best saftey in the NFL. These guys have to be able to react to the initial hit from the WR, start running, maybe to even catch up, and then make the tackle in open field. You don't need height for any of this. Then if your really good you get to go head hunting. Possibly a saftey blitz.