Do you guys do most of your structured intervals on the trainer? (2x20's, 5x5's, etc..) I am finding in incredibly difficult to do them outside with the PM. The terrain is always changing, power jumps all over the place (1 minute I am doing 375w up a short incline, next minute 150w descending), and I can't get a hold on whether or not I did, say, a 1 hour effort at 90% until I get home and download. It's like a crap shoot.