Just anecdotal, but my wise old coach would use v02max training (intervals of 4+ minutes at v02max pace with full recoveries) as the final stage of our plan. He claimed this type of training was like the icing on the cake and basically give small bumps in performance if used appropriately, and also that prolonged training with these sessions had diminishing returns. We'd do these workouts in the last 2 weeks of our training. Compared to our high volume training from early in the season these workouts were not actually that draining, but they do hurt like hek at the time!
I have a hard time reconciling this approach with the idea of stopping the intense v02max sessions 3-4 weeks before a race frankly. My only hunch is that Smoove views v02max interval workouts as the backbone to 5k training plan. Whereas my coach viewed aerobic training as the backbone to 5k training with v02max only used in the final stage to squeeze out 1-2% increase in performance. I frankly just see this as a philosophical difference that's appearing in this thread and is not easily reconciled with the existing evidence and research. What is apparent after following the training threads on letsrun is that very little is known about what works and what doesn't work, not to the fault of the letsrunners, but more a lack of research.