I'll just copy and paste as I feel my post answered these questions.if they truly believed they would have recommended it by the summer...but of course they needed a reason to explain why cases were still exploding despite mask mandates
if they do really believe it then how many lives did they kill by not saying this for a year
I'd say wearing 2 masks would likely be more effective, but not enough of a difference to make a mandate necessary. I'd also say, as evidenced by this thread, there would find too much public push back. It would also not stop the spread from maskless interactions, which is most likely the most common cause of spread.