Last winter I did 2-3 x20s@FTP. 2x with a tempo session and group ride every week. Pretty much peaked in the off season and suffered through the season. I think this winter I'm taking a longer break and going to start doing pure quality endurance rides up this 45 minute climb. I figure I need to work up to being able to do 3 hours of quality work. I think intensity is important to do like every other week but workouts at FTP are too much for me, plus I completely trashed my sprint.