I like the way you’re thinking. Some brief (lol) comments.
The Joyner paper linked to above suggests that “longer” (3-5 minute) “VO2max” intervals, and more time accumulated overall near VO2max were associated with better outcomes. There is another upcoming published meta-analysis from a different group that support the finding that “VO2max” intervals >4min are associated with better outcomes.
The rationale given is related to typical VO2 onset kinetics (as you mentioned) taking 90-180 sec, averaged to ~120sec for a trained population. Therefore at least half of the “long” 4+ min work duration can be assumed to be performed near VO2max. It’s a neat, simple way to categorize VO2max intervals, IMO.
You’re right that classic “VO2max”-type intervals will necessarily also burn a lot of anaerobic energy, but the systems are all interrelated. The major (I don’t want to say exclusive, but I can’t think of a counter-example off the top of my head?) stimulus that leads your body to ramp up to VO2max is depletion of ‘anaerobic resources’ and disruption of metabolic milieu from ‘anaerobic byproducts’. Functionally I would suggest you can’t get one without the other.
I don’t know what the current thinking is on how total energy breaks down btwn aerobic/anaerobic through a “VO2max” workout. It’s quite difficult to actually measure during severe intensity work (>CP/FTP). Simple stoichiometric equations break down for RQ ≈1.00. The 2006 paper quoted in the first TP slide seems reasonable enough, but I personally think the second slide is a bit outdated (related comment below)
I do know there are various compelling rationale for both ‘more than you think comes from aerobic’ and ‘more than you think comes from anaerobic’… which each have super interesting implications!