I'm just making this up as I go along now. I'm doing 1 hard, 2 moderately hard and two zone 2 sessions a week. Hard one is a race or event on zwift, moderate ones are workouts on zwift, but I'm making up the zone 2 ones myself. I can hold over an hour at 70% of ftp with much less upward drift of my heartrate than I could a month ago. I've been trying to put some variety into these sessions, today I did cadence drills. 5 mins warm-up then a steady 155watts for 10 mins each at a cadence of 70,80,90,100,90,80,70. Then 5 mins cooldown.
The turbo allows you to monitor small adjustments much more readily than on the road. For instance, moving my hands from the tops to the hoods drops my heartrate by 2-3 beats. It must open up my chest to get more oxygen in. On the road that would probably be countered by a wider frontal area increasing drag.