Hey @otoman. This is part of the subjective nature of working above (well above) FTP, and one of the key reasons we at TR have certain future plans in place and are working toward them as I type this. I’m not trying to tease so much as let you know we recognize how failure rates vary from rider to rider based on the type of workout, how their FTP’s relate to their aerobic capacity, recovery rates, age, gender…the list goes on and on.
For now, down-modify the intensity as necessary. This can mean an overall 5-10% reduction at the outset, a later reduction as you fade, starting low and finishing high, plenty of ways to still get quite a lot out of workouts that would otherwise bury you without some minor tweaks, just don’t get too liberal with the reductions. 