I found the video very informative! So happy to hear somebody else gets beat up by long rides that include long sessions at threshold, but kill the 1 hr HIIT sessions. I'm going to re-arrange my weekly training schedule to give me a rest day following the long ride with threshold efforts. My schedule currently has week's longest All Z2 ride the day after the long threshold ride. That longest Z2 is the workout that I've most regularly punked out on, for example, quitting after 3.5 hrs of a planned 4.5 hrs.

Maybe this is typical, but what I've learned about training from the more experienced BF folks is how and when to rest. This video helped advance that knowledge.