Originally posted by Mharr:

I had no idea the table only stored one player's pins at a time. That's not really signposted in game.

Does it combine everyone's explored regions as you'd expect or is that kinda janky too?

Yeah, uncovered map data is shared between any players so long as they touch the table, no matter who adds what or when. (Only after they've added it, obviously. It doesn't auto-refresh already-shared maps.) But the pins you get are only those of whoever touched it last.