BUT...
Bingo! Give me football players, not track stars and workout warriors. (Having said that, I do like watching the combine)
Mayock said on the broadcast, that smart teams like Pittsburg, Baltimore, and New England hope good players have slow 40-times etc. at the combine. That way they drop right into their laps.
It would be an equally big mistake to undervalue what you can get out of the combine as it would be to overvalue its importance.
Let's look at forty speed, for example. What it tells you is that Linebacker A runs really fast. Period. It's an important part of his skill-set (& in general, it's better to have a fast guy than a slow guy).
But speed is only one part of the equation - toughness, reflexes, diagnostic skills, coachability, size, strength, motor are all important. In fact sometimes freakish size, motor or diagnostic skills can be good enough to overcome slow speed. (I do suspect, however, that it's possible for a dude's speed to be so slow that no array of other superhuman skills is going to going to save his butt). Each player has a minimum playable speed threshhold based on how it fits into his total set of skills.
It's fashionable to slam the combine as "unecessary", "boys in shorts", etc. etc. but I think it does have significant value - especially when an owner is investing a gaziliion dollars each year in human product.
It' s just not an end-all.