Thanks - do get this point. As with all of this, it shows that different are approaches are rarely “right” or “wrong”, but often just better at accomplishing different things. Likewise, there’s always the issue of following protocols incorrectly (e.g. doing over unders “too hard”), which is separate question.
Should probably be more specific: if your primary focus is to raise your power at MLSS, and your TTE, then might there be some rationale for prioritising longer threshold work - especially if you find you can get more work done if O/Us particularly wipe you out?
If your target events are long TTs, which won’t have any long periods spent over FTP, then there’s less priority to be accorded to an ability to cope with the physiological processes associated with riding over FTP. If you’re racing road races with lots of hard efforts, though, there’d seem to be more reason to prioritise O/Us.
Aware it remains complex because obviously being over or under FTP isn’t a neat distinction, there’s still anaerobic work being done below or at it, etc.)
Rarely one way to skin a cat and a lot depends on the individual and their specific goals. Definitely don’t mean to imply that O/Us are “wrong” - more wondering whether there might be case to de-prioritise them if you’re chasing, above all else, an increase in (TTE@) FTP.