I don't have any Krein regrinds, but I can speak from my own knives I've thinned out. I have an Endura 3 and a Byrd G10 Cara Cara both ground flat to the stone, no microbevel or anything. I haven't had any durability issues with either of them, nor other knives I've taken to thin edges (SAKs, Buck knives etc). With the Byrd I've done a lot of woodworking. Lots of whittling and shaping. Slipping with a cut and smashing the edge into a knot, things like that have occurred with no damage visible to the edge or detectable with a fingernail test. I've batoned with it too, though I really don't think this is as stressful of a knife as many make it out to be.
I listened to Cliff champion thin edges on knives for a while but never acted on it. Nowadays I won't even carry a knife unless I've severely reprofiled it. Most knives I own I've ground flat to the stone. All my SAKs get their edge angles reduced by about half, my Buck 110's and 112 go flat to the stone etc. Really, I see no reason why a person like you or me should not do this. I can understand a knife company putting out the obtuse grinds they do with how an "average" person tends to treat a knife, but someone who knows how to take care of a knife should go for the super thin edges because he knows its limits. The increase in cutting performance is phenomenal. One thing in particular I like about the thin edges and whittling is you hold the knife at a more natural angle compared to when you use a more obtusely ground knife. Instead of angling the knife away from the direction you're cutting, you angle the blade downwards, the direction the cut is being made. It makes the work so much more comfortable for this fact alone, much less how much easier the knife will cut through the wood with the thinned edge.
I think it would make a lot of sense to have some super-thin sprint run knives, since these are generally either bought for collections and never used (Edge durability no issue here obviously) or bought by people who know their knives, and thus would be able to correctly handle these types of edges.
I challenge anyone reading this to grind one of their Endura's or Delica's flat to the main bevel and go cut some cardboard with it. I sincerely doubt you'll ever want to go back to the stock grind.
