The 40-yard dash is a big part of the NFL scouting process.
But it’s very important to remember one thing.
Say a linebacker runs 4.5, but has bad instincts, or doesn’t have the playbook down, he will look like he’s playing more like a 4.9 guy.
So good forty times only matter if the players plays to that speed.
And part of that is knowing what you are doing between the white lines.