I have created a little write-up of a Xert breakthrough using a Ronnestad workout - all done in 26 minutes and I could have skipped a six minute cool-down. I am doing my best to publicise Xert
https://sixtyplustimetrialling.wordpress.com/2020/06/19/analysis-of-a-xert-breakthrough-session/
Feedback welcome and even better follow the blog. More Xert stuff coming shortly
cool stuff… i like the numbers as well… I no longer like ERG very much… could give it a go on the open road i guess… my toughest workout similar to that was 5x5’ of 30/30’s with the extra recovery i did a lot higher than 130% FTP consistently for the 30" average. but the lowest i was able to bring my MPA was 56% of maximum… to break through i would have needed to push my peak power for the 5th 30" interval to roughly double of what i actually was able to do…
higher power is more sprint (HIE and PP) focused i think? so ronnestad workouts with the lower rest must be more aerobic focus? not that either of them is really purely going to improve TP…
Thanks for sharing and well done on the BT 
Only comment I’d have is that you don’t necessarily need to follow the 130% and 50% targets precisely… I actually just go near enough to all out each time (seated), and spin in between… the aim should be that each interval is roughly the same (if possible!) and 9 or 10 out of 10 RPE, but whether it’s 130% or 140% or something else is less relevant and indeed dependent on yr signature e.g. those with high HIE may not even reach BT by precisely following those targets… for that reason I don’t use erg mode at all.