[lamontcg]

> Qualitatively the vaccine alone does not work well enough to lead to an R0 < 1

I honestly haven't seen any evidence of this.

With Alpha the attack rate for 80% of breakthrough infections was zero and the other 20% were only 1-3 cases. That's enough to drive the r0 down below 1.0 in a 100% vaccinated population. Nobody has done similar studies against delta breakthroughs.