Sorry I am likely to confuse you even more :)…
So, I am big Maffetone fan, and while I love Seiler’s core message, and he proved at some level that in the short term his 80/20 is better than 4 weekly sweet spot workouts. I think the main advantage of Seiler’s approach is it is a dead simple training plan and it is a reasonable approach. I think it misses some core fundamentals of training. So I believe unless you are seeking dead simple annual training plan with no periodization I don’t think it’s optimum, but at the same time their is no “proof” that what I am suggesting is correct. One of the big benefits of hard VO2max training is that it taxes both your aerobic system and your anaerobic system. This produces fast results to reach peak performance. Long term you really only need to reach peak performance prior to race or event season which for most here is outdoors in the late spring.
So optimizing short term anaerobic gains for a long time does not make a lot of sense. It causes a lot of stress with limited benefit. You can only improve anaerobically for about 8-16 weeks. So taking more of a progressive approach makes a lot more sense. And focusing your hardest efforts (including 4X8) to a peak period of training. Also I would say very few elites follow Seiler’s training approach. I agree 100% they are polarized in their training intensities but almost all have a much more heavily periodized approach with more variety in training intensities and types including many or most still do pure base periods (no idea what %).
So for Seiler, he likes indoor Zwift races year round I believe, so really for him yearly polarized makes a lot more sense. Keep in top form all year round without burning yourself out. But I don’t think this optimizes for long term to get small increases each year, it’s much more likely to peak and just stay there.
So if your desires are closer aligned with what I believe his are then it’s likely good.
So with regards to Maffetone, I think you are missing one of the most fundamental points he makes. Which is start pure 100% below AeT (low heart rate) training and monitor your progress with MAF tests. Seeing continual improvement between HR/power ratio will inspire you to keep doing it, once you start seeing this improvement then you can try adding in more anaerobic or hard training 1 day a week and see if that stalls your aerobic improvement. If it does STOP and go back to pure base. I personally have gone through and witnessed both the progress and the stopping of progress by adding more and more intensity.
You could try by starting with this hybrid approach but then if you are not seeing aerobic progress because you are not following Maffetone’s suggestion everything gets a bit more scary and you might think you must go back to traditional training… If you sleep very well, get super good recovery, low stress life, not too old and do his fasted zone 2 rides, so everything correct except you add a 4x8 once a week, the risks are reduced that you won’t see progress.
So I would say either you buy into Maffetone or you don’t I think if you understood how small the risk is you would jump into this no problem. You will start feeling out of shape and this is scary but hopefully you starts seeing MAF test progress before that happens, it lowers the scariness
So I know I have not answered all questions here, but helped give something to chew on.