Have you ever been cutting anything for a long time, and dulled your knife to the point it wouldn't cut the material you were cutting any longer?
Only time I have done it was cutting fiberglass insulation. Dulled Case CV before I could even get the two segments of the batting installed. I knew it would because the guys I worked with just used Old Hickory butcher knives and sharpened them between every cut with a bastard file, but I just had to see for myself. I haven't tried, but I sincerely doubt even the best super steel would width stand that stuff.
Just curious because I can't think of another time I've cut enough of anything to COMPLETELY dull a knife out.