In a high grade lock down, masks won't be the key driver of keeping the R number below 1. The lock down is.
As lockdown restrictions ease, we need to look at complementary strategies to keep that R number below 1.
The quality of the mask doesn't matter IMHO. It is worn to prevent the wearer from spreading large or small droplets around the place whenever they cough, sneeze or say a word with the letter P in it.
Ontario needs to stay on their current point on the graph. Masks can help them do that.
So what happens next in Sydney? Infected people from Melbourne have been walking around the shops and travelling on the buses for some weeks now and they didn't wear masks. Sydney could be lucky or unlucky because infected people appear to shed virus at different levels. If only a small proportion of infected people are super-spreaders there is a chance that there are no super spreaders in Sydney. It's a toss of the dice.
BTW. The spread through a Melbourne school refutes the amateurish government study which claimed that kid don't spread it. I called the study out as nonsense in March because the sample sizes were too small.
