I’m trying to understand something.
I’ve created a custom workout Grasshopper. It’s 4x1-minute threshold efforts followed by four 12-second standing “all out” sprints at 300% FTP, with 4-minute recoveries in between.
It’s intended to be hard, but definitely doable. In fact, I was able to complete it and thought it could be made just a touch harder… Then I noticed that TR gave it workout level 28.7. That looks high!
What gives?
I believe this is a known issue for custom workout creations that is yet to be resolved. Perhaps @IvyAudrain can share some insights as I recall this being brought up several months ago, but never saw if it was something the team had fully addressed.
Yup, levels for custom workouts are known to be wrong, wrong, wrong.
I think a lot of them for longer intervals work pretty well. I just did a 3x20/3 at 90% that was a 6.6. Eclipse is like a 7.0.
WT actual F 
If one can theoretically ride at 100% of FTP for an hour then 200% of FTP for 30 min should be doable, if not it means your FTP could be set too high.
Uuhhmmm…no? 
Based on that logic, Tour riders can do 1600-2000W for 15 minutes. Awesome!!
The PDC is not a straight line
By my best educated guess, I believe this is particularly a problem on workouts that target multiple zones, not necessarily custom workouts.
For example, your custom workout has a few sprints, so it got tagged as an anaerobic workout.
But it has a few threshold intervals in the mix, and these are bumping up the level of the workout.
I made a custom workout a while back with 4x15-minute intervals at 95% FTP. This got marked as a 5.3 Threshold workout, and that seems reasonably accurate as far as I can tell.
On the flip side, look at the workout Ragged +2, this is an official TR workout. It ramps up from 60% to 100%, spending a total time at threshold for about 13:30, but this is tagged as a 5.5 Threshold workout.
Makes sense. It’s also probably 300% FTP. All official workouts top out at 200% max.
Here’s the workout in question, btw. Doesn’t seem all that impressive.
It’s probably like you say, if the official workouts top out at 200% then it probably doesn’t really know what to do with 300%.
That SuperTaku one is not feasible…
That’s something I do regularly too. Mostly to increase my TTE @FTP. Pretty simple strategy where I start with a relatively easy 20min @ 200% and slowly build that up to 60min @ 200%. Once completed I do a RAMP test to see if my FTP increased. 100% can recommend 
I think you are right about the 300 % of FTP breaking it…
I couldn’t quite do 6x30s @300%, but I might scale it down to 280% and try again…
20 minutes at 200% should not be “relatively easy” - if you can it implies your FTP was set badly, badly wrongly!
The standard/traditional FTP test is based on 95% of 20 minute effort. (or 90% the 2x8, or I believe the ramp uses 75% of peak 1 min power). My FTP is around 280, so 20 mins at 200% would be 560 watts… I can’t do that for 2 minutes let alone 20…
If you are doing workouts like SuperTaku, your FTP has been set incorrectly.
Edit: I realise you are probably taking the p!ss…
Yeah, if I had to explain it was meant as a joke it probably wasn’t funny. My bad.
