I did huffaker earlier in the week, I believe it was 6 intervals of three minutes at 110,115,120,120,115,110 and it was super tough. I managed to complete it which gave me a huge sense on accomplishment but I was definitely struggling to complete each one.
Also, as a counterpoint I did Clark on Thursday which was a set of 7 minute intervals at around 95% of ftp. They were very uncomfortable so I can imagine that six minutes at 110 would be grim