Just my perspective.
Looks like he recharged 7 times in all, with 6 of them in the last 5.5 hours, most or all of them from 50% to over 80% or even 90%. He also was driving pretty fast, while using the heater (which, in my experience, puts more demand on the battery than the AC). He was doing a lot of climbing, looks like about, 6,200 ft, and probably also doing at least some intermittent charging, with regen, as he also descended about 4,500 ft., on the Corvallis-Ashland trip.
He got to 9 bars of heat, apparently right after the seventh charge, which was from over 50%, to 94%.
And it apparently dropped back to 8 temp bars, sometime during his drive, to the next stop.
Is that totally unexpected performance?
Is it much reason to worry about more conservative driving, and charge, activity?
I would think that after the battery heats up to over 120F, it will be pretty hard to heat it up much more, as long as the ambient temp is at least somewhat lower. And wouldn't the LEAF probably be designed to protect the Battery, by limiting the charge rate, before the battery got hot enough to restrict power use, in subsequent driving?
I expect it would not be too good an idea to try this long a drive, with this much high battery charge state charging, in high temperatures. But I don't think we'll really know too much, till someone can try a long hot trip, later this year.