I'm sure that doing small things like destroying a special guard post would be fine.
It's generally accepted in our games that those all need to die if they're in the way. Distribution nodes and warheads and other small things all get discussed, though, even if it's just mentioning them and making sure there are no objections.
I suppose it depends on how many players are in the game. A game of two players can sometimes be apart, while a game of 6 players needs the smallest "unit" of players being 2. That pair would have to have their fleets move together whether it be for offense, even for one post if the fighting is vicious enough (I guess).
Early in the game, we can get away with doing some stuff individually as long as we're prepared for waves and whatnot. The closer it gets to the end, the larger the "units" end up being. We're near the end of our current game (not sure yet if we'll win or lose), and a lot of stuff requires three people. Sometimes that's not even enough. I haven't even gotten to go along on most of the past several trips into AI territory, because we need at least one person on active defense with the mess we're in.
