Wow, yes–that’s quite a mark! I’ve seen temporary impressions on players after they played in the extreme upper register but that mark seemed to hang around and is red. Greg or someone else might be able to identify what’s going on there.

I like his playing too, thanks for sharing. Here’s a couple I’ve run across that I enjoyed, more on the other side of the spectrum but a good example of what appears to be relatively effortless playing by Caleb Hudson (Canadian Brass) and Chris Coletti & The Canadian Brass: