Hahaha! Just got the chance to revisit this; today was my first day off in about five weeks.

I agree that some factory knives ship with "burnt" edges. I don't think it's common and when I do see it the damage is usually fixable by sharpening the blade a couple times. It's a pretty good rule of thumb that if the edge feels hot while you sharpen you're risking damage to the edge. But while you can overheat an edge with just sandpaper you can also keep an edge cool on powered equipment. Even a very high speed grinder is safe if contact with the belt is kept brief. This is especially true when using fine grits- they're easier to burn the edge with.

I think you'll find that using a grinder like the Kalamazoo with 80 grit Blaze ceramic belts you'll be hard pressed to burn an edge before you've ground the knife down to an ice pick.