Light infantry foot mobility standards?

[Rifleman]

Before WWII Fairbairn and Sykes made the same observation about police qualifying with pistols. They stopped keeping score at 50% hits on the target to avoid qualifications becoming sporting events.

I can see their point but other top cops have disagreed.

For instance, some members of the now defunct NYPD Stakeout Squad used to shoot competition and thought it helpful for stress inoculation.

Now, how did we get here from foot mobility?