For me, it is a factor. I don't usually drink barrel proof whiskeys at barrel proof. I add water to them, almost always. At the high proofs the BTAC barrel proofers, I can't taste anything but alcohol. Cut down to the 90s or 100s, I can taste a lot more. Plus the massive, painful heartburn that follows makes me miserable for hours. So maybe this discussion says as much about how people drink their whiskey as it does about Saz Jr & Handy.
I'm with you on always cutting high proofs. Not as low as 90 but 100 to 107 proof. Also not the biggest health nut (or would I be here) but I do wonder if down the line there may be some damage if one is regularly drinking high proof, even in moderate amounts. I know above 107 proof, my tongue and back of throat are feeling things that don't happen below that. As to heartburn...that's why God invented man who could then invent Omeprazole .