He said “All Out” you say ~120% and I think that pretty much explains the level of daunt. TBH I’m not a fan of either version too frequently 
but a peak and fade type interval is much harder than a steady state interval.
He is a steady state monster but he’s pretty solid at his 3-5 minute power too. I knew I had seen some of his HR and lactate numbers on here before and ironically I’m quoting you:
Pretty insane and it will be fun seeing him attempt the hour record.