Indeed, even the practice of calling certain vaccines "2-dose" or "1-dose" is somewhat arbitrary & misleading, reflecting rushed early decisions about which cou

Indeed, even the practice of calling certain vaccines "2-dose" or "1-dose" is somewhat arbitrary & misleading, reflecting rushed early decisions about which courses to test. The Pfizer/Moderna mRNA vaccines might be just as effective, 30d-onward after one dose, as the "1-dose" J&J. The tested 21d/28d spacing for the mRNA vaccines might be far shorter than optimal, so the ad-hoc "emergency" delays of booster shots by many jurisdictions might actually be benefitting long-term immunity. The "1-dose" J&J might benefit greatly from a booster 30d, 90d, 180d later. Even the dosings could be far from optimal, with some hints that half or less of the mRNA vaccines may be just as effective, especially in younger patients. And of course there was the AZ/Oxford glitch that mistakenly gave half the intended dose in the 1st shot - & that subgroup seemed to have even less disease after the 2nd full-dose shot. (While this could be a statistical fluke, maybe also a "booster" that's stronger is read by the immune system to mean that the disease is continuing to become even more of a threat, so it reacts even more strongly than to a "same as we beat before" dose. Until lots more study is done – who knows?) So: people who treat the officially/rigorously evaluated doses/schedules as "optimal" or "the only safe course" are way overclaiming what the data shows. They data we have are a series of singular draws from the possibility-space, showing some points of reasonably-safe and -effective approach. With plenty of other data constantly arriving, hinting at other equally- or more-effective approaches, regions & practitioners should be free to use their best-judgement to navigate risk/reward tradeoffs.