I don't know how many people have seen this thread I bumped it tonight: https://nfl.myfootballnow.com/forums/4/1763?page=1#8112

The gist of this thread is that there is a minimum speed where the parabolic curve flattens to a point where there is not much difference between a players' SP and a player with SP+10.

What is it already?

Minimum SP: 68

Once a player hits 68, there is functionally < 10 points difference between a player with 68 SP and a player with 100 SP.

The reason why players accelerate away from other players has to do with body weight at that point and how weight impacts acceleration. (Also in the thread.)

A receiver with 85 AC will always accelerate faster in the open field without the ball than a LB.

Wait, why the bold and italics. When the linebacker is in coverage, the roll that matters more is the B&R vs the B&R Avoid. The longer the linebacker holds that B&R win the longer the receiver takes to accelerate.

Once the receiver or the running back have the ball, the roll that matters is Ball Carry. Players with higher Ball Carry maintain their speed throughout the run while players with lower Ball Carry slow down. This has been demonstrated consistently since the game started.

So if you take away anything it's that once a player reaches 68 SP the thing that matters more in who gets ahead of who is acceleration.

Also, CBs are playable at 40 SP at CB1 but that's only because the game only throws hook routes there.