I ride a LHT and spend most my riding time traveling up and down the local hilly back roads with their 3 to 500 ft elevation gains over 1 to 11/2 miles. I travel partial loaded with day trip stuff which probably adds up to 10-15 lbs and spin 13-14 mph 20 to 50 miles 3-4 times a week. I'm a 5'10 187# geezer.
I'm getting a bit fitter now and want to try a few different types of timed events this year. In preparation, I would rather just Fartlek on the Surly :-) then go on serious specific training rides on a sport bike.
This is a valid enough way to train, yes?
Secondly, my thinking is since I won't be on it much, good stiff bike that can take my weight and climb would be a good choice....the heck with the comfort.