I think this is related to "saccadic masking".
I sometimes look twice on my toe-side, I just don't trust myself to catch everything.
AND I STILL GET CLOSE CALLS. I am terrified during touron dense periods, like spring break, USASA nationals, etc....
I know some people here trust their vision of catching everything on each turn, and will continue the run with someone behind them. I will almost never do that.
https://navalsafetycommand.navy.mil/Portals/29/LL 18-18 Why Don't We See Motorcycles.pdf
https://scienceofbeingseen.org/2021/11/06/invisible-motorcycles-its-magic/
My take is, if you spend enough time on snow, you are almost guaranteed a collision. I will do as much as I can to prevent it. But statistically, I'm in for another collision. I got whiffed the other day at Loveland from a guy that saw my run. We looked at each other, I started carving, he was watching, watching.... turn turn turn... freeride-world-tour brah straightline pass. I didn't even see him coming despite checking every turn.