What a bizarre thread!

First of all, it shouldn't even be called a lock washer because that's not what it does. A lock washer is usually splined or split and it is intended to keep a single nut from loosening.

This is more of a spacer. Some are tabbed in an attempt to make the adjusting process easier, but the real action is the two nuts tightening against each other, and you don't need a washer for that.

The bearing pre-load is a function of how tightly the upper race nut is adjusted before the lock nut is cinched into it. As long as the two are tightened properly the preload will not change.