Over-Under intervals predicted vs earned XSS score

I’ve noticed that on most exercises, the actual/earned XSS score comes out slightly lower than predicted, and I always assumed that was due to not holding target power, or downhills, or traffic stops. The difference is typically relatively small. However, on Over-Under intervals the difference comes out rather substantial. The predicted XSS for me is 213 (so I expected to get something in the 170-190), last week I got something in the 130’s. I assumed that was because I felt tired and had a hard time with it. Today I tried following the target much more diligently, and still had 137 by the time I was done with the work out (which went up a bit more for the ride home). I also noticed that while the workout is supposed to take 1:58:42, I was done in a little over an hour an a half. Is there something I should be doing differently in order to ratchet up my scores?

The Over-Under Intervals workout used Target MPA for the duration of the intervals. If you do the high-intensity intervals too hard, you’ll finish them sooner. Similarly if you do the rest intervals too easy, they too will finish sooner. Performing the intervals like this will reduce the overall XSS of the workout.