That's very interesting. I've not heard of any considerable wear happening on any sear...ever. Would you mind posting some close up pics of the sear so we can get a look? My go-to guy on sear related stuff is Mike Otte, of Michael's Machines. I know he did a lot of work and research on hardening while building his 23e guns. If he doesn't do that work he certainly knows someone who will.
Good luck my friend - and please keep us informed on the outcome. This one is curious indeed.
Mike is @hk21man on this board if you did not know. He's in the vendor section.