I forgot to mention that with the tremendous hills yesterday came some brilliant descents. These were real point-the-bike-and-hold-on-for-dear-life drops, and I broke the 40mph barrier on 12 (yes twelve!) different occasions, maxing out at 51.8mph!
Also, when the total ascent went over 9999ft I discovered a bug on the Garmin 800. It justs displays “—-” even though it correctly records the ascent. Bizarrely, total descent displays fine over 9999ft. So if this happens to you it’s “normal” – I have reported the bug to Garmin so we’ll see whther that gets ironed out in the next firmware update.