Update: the answer (for me personally) turned out to be 1.65
Mount Washington: 01:32:08
Alpe du Zwift (PR): 00:55:52
The Mt Washington Hillclimb was amazing. No harder or easier than what I’d imagined it would be - just an almost unrelenting 12%-15% hill from start to finish. The few times where it dipped into single-digits were short, few, and far between. Visibility for the last mile was essentially nil thanks to dense fog/cloud cover. Loved every minute of it!
In 2019 (July 14), I completed the Mt. Washington hillclimb in 2 hours and 11 minutes. It was a cool day, the top was a little cloudy, a little windy.
Today, I completed the zwift Alp d’huez in 2 hours and 13 minutes.
I was in better shape in 2019. For the real climb, I didn’t change my bike gearing or do anything special to prepare aside from one ‘training ride’ early May 2019. I took my bike up and down the auto road at Miller State Park/Pack Monadnock 6 or 7 times, so I was reasonably confident I’d be able to handle Mt. Washington. I wasn’t racing to win, I was racing to finish–which I did. Comfortably. Although, when I remember some of the steep sections, I have the uncontrollable urge to weep.