Thank-you for explaining.
I'm going to play devil's advocate here. While I understand and agree that edge geometry had little if nothing to do with that knife being able to scratch glass, I think it could have something to do with how much or little edge degradation resulted from making the scratches. It would be interesting if someone could come up with a controlled and reproducible experiment to proove what's what regarding edge geometry vs. heat treat/steel composition and how they affect performance.