Extracts fall short of ample science:
"Cloth face coverings may help prevent people who have COVID-19 from spreading the virus to others."
"Cloth face coverings are most likely to reduce the spread of COVID-19 when they are widely used by people in public settings."
Whilst it seems logical at first sight many people would also think it is logical that a big stone would fall faster than a medium sized stone.
Anyways it sounds as if the Llama is going to come to the rescue.