Agree with Larilli's answer, and it goes for the Valentine's Event too, Co-ops are just not an option since Unity was inflicted upon us.
Even if the map loads for you without freezing in a zone refresh loop or kicking you out of the game with script errors, it will be happening to the other participants, and as it always was with Flash, trying to coordinate 2,3 or 4 players dragged the game performance down, in Unity's case that means getting all players to complete the map is unlikely in hours, even days.
Urd also makes a valid point, even with this unholy mess, BB still don't listen, they didn't even when the guild quests were serving up impossible "out of level" quests which caused ructions within guild as frequently you could not complete the same quest over and over again until you'd gained another 2 levels.
And with Sandycove's chat falling apart on a regular basis, trying to do anything team-based is nigh impossible.