I would accept a similar kind of reasoning in an argument towards caution, but not in an argument for seeing what happens with prolonged partial but insufficien

I would accept a similar kind of reasoning in an argument towards caution, but not in an argument for seeing what happens with prolonged partial but insufficient immunity. Aside from near certainty that a change to the target protein is game over, we have no idea what other mutations could render immune responses triggered by the vaccines worthless, and I don't see the ethics in an experiment to find these mutations.