I have a story from when I started TR last September, I did SSB LB. after having followed the talk on the podcast I really wanted to find out how over-under workouts felt and try them ASAP. so I did Reinstein from the MV plan instead of some other workout I actually had planned.
so far so good, but at the same time I was still figuring out if my training zones were ok. My ramp test went fine, but people had said that it may take a few ramp tests to get used to it. I felt during the workouts and from my prior training experience that I probably could hold 1-2% more intensity and still be in ‘sweet spot’ effort range. so on the day I did Reinstein I decided for the first time to go with 105% for the whole workout.
I made it through, barely hanging on, but I was totally spent afterwards. my legs were completely emptied. it was a lovely, sunny day outside so I decided to walk through the neighbourhood and go for a coffee. after reading the newspaper and chilling for an hour or so I wanted to get home (~10 min walk) but there was no way I could make myself walk again. I ended up getting an uber, totally ridiculous for that small distance. I was pretty sore the next days.
of course I finished the workout, but this would not have been pleasant on a regular level. I considered it a worthwhile lesson and went with 103% intensity for the rest of the block.
so my message for you from this: sounds like you can hold more than your 100%. I would try how other workouts go at 103-105% and if this is fine keep it, maybe even try a bit harder %. don’t retest, rather keep doing the workouts and adjust as you go.
doing a workout at somewhat less % intensity than your absolute max will not reduce the training effect a lot so there is not much harm in having a little less %.
by the way, today - after many months of TR - I look at Reinstein and think, such short over/unders, looks so easy, how could that have happened?