[moneytide1]

The socially normalized buried nose produces an interesting effect when passing by someone in a hallway or sidewalk - the deferred acknowledgement:

I rarely have my device out while walking in order to indicate that I am receptive to an approach. When I see an incoming buried nose, I assume they are too busy and keep my gaze past them as they are clearly not going to be available for a nod or pleasantry exchange.

The thing is, after the acknowledgement window has passed and we are closing proximity, I perephrially see them look up at me at the very last second before passing.

Not sure if it's just me misinterpreting social circumstances, or if there's a new standard of interaction that I need to figure out.

[pferde]

I don't think you are misinterpreting anything. I think those glances are part of survival instinct, assessing whether the moving object they registered out of the corner of their eyes (you), that is getting near them, is dangerous or if it can be safely ignored.