You know, regardless of what people think, numbers do translate into on field potential. I'm not saying that numbers = on field success, but they do have a strong correlation with potential. And really that's all the draft is, trying to find players who you think have the best risk/reward ratio. If you take two players who are exactly the same except for the fact that one runs a 7.2 three cone drill and one runs a 6.5 cone drill there's an obvious advantage for the player who runs the quicker time, even if the 7.2 player has better footwork. I know it's cliche, but things like speed can't be taught but things like footwork in route running can.
However, if you draft a player who has physical limitations then you run the risk of that player not being able to translate his success against very athletic NFL opponents. Even if the player ran good routes in college and was able to get separation there's a good possibility that he won't be able to do the same things at the NFL level because his lack of "explosion" will be more pronounced.
Now, I know it can be said that there is no guarantee that a player with great quickness who runs poor routes will ever develop their skills into good route running, but it just comes back to the risk/reward issue. That's why I would argue that the formula is something that is somewhat reliable, it objectively measures, based on a players physical ability and past production, if they're worth taking a risk on drafting early or late.
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