It is probably not worn so much as just being stretched from over tightening the screw. This is a common problem, and I suspect the reason the Encore uses a different approach. I've had pretty good luck with just peening the dovetail slot down around the dovetail using a light hammer and a punch. While not pretty, and probably not satisfying for the purists out there, it is hidden by the forearm, and it works. It works even better if you use some super glue and don't tighten the screw so much next time.
RonF