Davej wrote:
I was just thinking... what if you added a few Gore-Tex patches on the
sleeves of a conventional drytop? Or wouldn't it make sense for them
to make drytops with just the sleeves made of Gore-Tex?

No, it wouldn't, as you still get significant breathability in areas
covered by your PFD. Patches on the arms would do almost nothing. Think
about it, how much do your arms sweat compared to your torso?