A deviated septum doesn’t entirely block air from entering or exiting your nose. Wearing a mask over their mouth is going to drive more air through the nose than if they just left it off and breathed with their mouth open. It’ll be expelled in a jet, going farther. If they’re internally closing their nose, or it’s completely stuffed up, then there’s no reason to uncover it.

As a person sharing airspace with them, it definitely makes me check to be sure my own mask edges are sealed to prevent me bringing their germs home to my vulnerable family member.

When someone is not masked at all, it’s pretty easy to spot symptoms that remind me to check as well.

I don’t really expect anyone to mask anymore but it’s counterproductive to half-mask.

I notice people give me extra space with my mask, because they assume I’m ill. That’s a winwin for me.