That stood out to me as well. There's a real opportunity cost to not moving more deliberately: those few extra months represent several hundred thousand lives lost. Could a vaccine be worse than that? Of course if the answer is yes, then that would be horrific -- you wouldn't want to vaccinate hundreds of millions of people and then discover that you've unintentionally shipped Thalidomide 2.0. But at the same time, the probability of such risks should be balanced against the certainties of what will happen without a vaccine.

Anybody who says that this is a simple or easy calculation frankly has no idea what they're talking about.