That means that you need to watch out for trouble, and trouble is anything that puts you out there on your own. You never want to be left to your own devices. You don't want the swim to be a time trial. No race of truth here. You want to glom onto somebody else's ability.
People bunch up in the turn, and they spread out on the other side of the turn.
This is the place people often get dropped. If you know that this is coming, and are prepared for it, you'll be less likely to get spit off the back of the swim pack. In general I'm not one for getting physical with others during a race, but I'm jealous about feet. If a good set of feet come by me at the right pace, I might be inclined to move onto them. I've perhaps been known to nudge that person off, and take possession of these fine feet myself.