I'm with you, 40's and any contest off the field is just not football to me. I like Brandon Spikes, he can play the game. I'm not sure he is the next big thing in NFL, but i think he will be a very decent LB at least, worth a pick.
The real problem about all that, and the reason that 40's will always be relevant to football is that among the best football players, there will always be some that just happen, by chance, to be really fast off the field, on straight track. These players are good because they can play football. They just happen to be fast off the field as well.
Boldin was running a 4.7 or something. Spikes a 5.0. Since LB's are supposed to be arround 0.3 slower than WRs (what a great logic huh) , then i guess in theory, Spikes can still be good LB in the NFL
The logic of 40 is made up, simply because you will always be able to wrongly interpret the real reason why a player does succeed in the NFL.
It is defenitely also the huge desire to be able break something difficult as football down in numbers, so it becomes simpler to understand. The evaluation is so hard, and sometimes so impossible, that it is a human trait to look for the reason elsewhere and get some numbers for comparison, even if there are some major issues with them. From time to time, offcourse some players will excel at both football and the 40, and you will always be able to go back and say: The 40 yard dash is indeed important. I guess you could also chose what type of icecream is the favourite one of all the prospects. Sooner or later you will get a future HOF player that happens to like banana taste the best, and you can say that this is why he is great.
Seriously, look in the HOF. The distribution of fast players on track vs. slow players on track is probably just arround the same as the distribution you will find by just looking at, let's say, all the players that are declaring for any given draft year. Those that succeed and those that not.
I jus't don't agree that Spikes will be able to replace Hayes. Hayes is the FB of our defense. He lines over the FB and it is his responsibility to shed his block and still make a play. His job is also to deal with Lineman that get acces to the second level with a jump through. Since we got a DD on our line that lets go many lineman to the next level, this job is really important. Spikes is more suited to replace Dansby while a guy like Micah Johnson plays exactly like Hayes does.