I used to read the yearly accident review publication by the American Alpin Club.
Two very basic facts emerge:
- about a 25% of the accidents they list would not have been accidents if a helmet had been worn
- a significant number of incidents are caused by folks splitting up for some reason
The large point that I've take into later life: there's nothing special about me that exempts me from statistics.
So when I can I wear a helmet while climbing and never split the party in the mountains.
And the logical extension would be don't go hiking with anyone who might split the party or strand you, I suppose.
Well, as much as one might.
Many of the very good lessons of goofing around climbing with randos has been refined skills at evaluating partners, which I had not previously considered to be a skill that could be developed in its own right and which has served me quite well as I have worked at it in my larger life.