Ok, I've got a wedge. It's warped. Not noticeable visibly but on a flat surface the concave side bridges about 1-2mm up in the center when faced down.

Would it be reasonable to attempt to grind it down on a bench grinder with a belt sander to get a straight wedge out of it again? I've been working on a XC dmt but at the rate it's chewing, it's not worth the time. I'm also not willing to invest in narrower hones (or try using my hones sides) to attempt to polish the concave side with the warp.