Being invited to some relatively large-scale seasonal gatherings and having to turn them down, my mind turned to the mathematics of communication.
Like, when there are two people, there is one line of communication, and when there are three, it's three lines. But when there are four, it's six lines. And you could map this onto potential Covid transmission vectors during a gathering of n people.
And there's a formula - and it's n * (n-1) / 2
So, our current state limit for groups is five people from outside your household at one outdoor meeting, which gives you 10 vectors of transmission.
But the limit for a wedding or a funeral (indoors, even) is thirty people, which gives you 435 vectors of transmission.
And, because we all fear God, the limit for a religious gathering is two hundred (or twa hunner if you're terribly Scottish indeed), which gives you an astounding 19,900 potential vectors of transmission. God wins!