Oh yes 
Doing the “Col de la Loze” on the 16th of July was exactly all of that. Now having said that, this is exactly where the HR based training comes in so handy. When I look back at this type of efforts, heat and height (and let’s be honest, also duration) have a big impact on your power numbers. But I paced it based on HR. Pro rides would not call this pacing, but that’s not my challenge. I was not interested in any “time”, I was interested in the experience and in getting the Gran Fondo done. Out of the 4 hours, I was about 90 seconds “in the red”. That’s it. I always have my HR and my 3s power on my Garmin and I adjust as needed. So yes : above 2000m, after 3 hours of riding, I didn’t do the same power numbers as I can usually do.
The point of the HR based training is taking that complexity away : I know I can do between 140 and 150 bpm “forever” (provided I properly fuel, which is a whole other story). So when I ask Trainerday for a 146 target, I don’t need to adjust anything. The app does that part for me. If I have a good day, power will be higher, if I have a bad day, power will be lower.
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