99% sure open communication is allowed. The extent to which it’s allowed is up to you, though. With my play-group we cut it off at “talk of general strategy is allowed, anything more specific is not.” We do it this way because of bad experiences where multi-player games would devolve into the “good” Axis Player and the “good” Allies Player forcing their teammates to obey their orders on what to do each turn, effectively turning the game into a 1v1 with a peanut gallery. That’s not much fun for anyone.
