I’ll hold my breath anytime I’m close to engines/tailpipes emitting anything. Sometimes I hold a full breath, sometimes it’s a half-breath. That helmet-related aside turned into a paragraph, then into a giant footnote, then I decided to tug the whole dialog into it’s own piece, and that is what you’re reading now. Then I ended up reading something that clicked as ‘oh, that makes sense’ as soon as I read it.