but when I take, eg., a two-hour ride that includes an hour on each side of it for getting ready and wrap-up afterwards, that's four hours gone.
WTF do you do for that hour before and that hour afterwards?
I can't imagine that much time and effort going into a ride preparation and debriefing - or whatever you do!! I am ready in about 5-8 minutes, even including kit when I use it.
Bibs on, jersey on, slip on the riding sandals, check and fill the water bottle(s), lift the bike off the rack, check the tire pressure - I only fill every 3 days unless I detect a leak, and then I have to fix it, but that hasn't happened much this year, 20 pumps into each tire if necessary, a quick safety check and I am off.
So, what is it that takes an hour? Each way?
(If I am not using "kit" I just jump on a bike with platforms and head out.)