Your claim of "0 data" is completely wrong. The original phase 3 trials already showed limited support for partial one-dose efficacy. (They even broke it down i

Your claim of "0 data" is completely wrong. The original phase 3 trials already showed limited support for partial one-dose efficacy. (They even broke it down in their writeups! That's non-zero data!) Observational reports so far on the tens of millions additional doses given (compared to a mere ~15-20K in phase 3 trials) is also suggestive of 1-dose efficiency. (Most recently, a retrospective study in Israel – the nation with the highest proportion of its population immunized – found 51% efficacy against "confirmed COVID" looking at just days 13-24 after a single dose – and that's in a world with far more variants than the original mRNA studies. It's reasonable to conjecture from other results that the efficacy would be even better later, and better against "severe disease".) Plus, there's everything we can reason about from similar diseases & vaccines. The reason to wait for 2nd-dose-plus-7d in study "primary endpoints" is to have a singular, legible, stark readout for rather-simpleminded regulatory processes. But smart people who live in the real world know the actual mechanisms are far more fluid/incremental, with immune processes starting immediately from one dose, then accelerating over weeks (even without a booster).