Not really. The sensor helps the system determine how much braking is still being effected with some tires locked and take advantage of it. In a non-ABS vehicle, you'll typically get better stopping on loose or granular surfaces when the tires are locked because the material can pile in front of the tire and form a dam of sorts. This is true in gravel, snow, sand, and dirt.
The sensor will determine at the moment of lockup if the brakes are still doing a decent job and will modulate less frequently to let small dams build up and lend their assistance.

Brent