Originally Posted by
Dawnseeker
Remember it doesn't cost you one of your 3 Sail attempts unless you actually begin the crossing, so the only penalty if you lose the map before you can get out of the boat is your attack cooldown of 5 minutes. No big deal!
If you are worried about someone taking your map half before you start sailing, then you can ask a more powerful member of your guild who has the other half to get in as soon as they see you in the boat. They don't need to wait for the battle to complete, as long as you're the winner.