If you need a drop on Acheron or instance or King Behemoth there's no point in even joining a party that's not at least 1/4 progress if you care about your time. Pretty sure all those withdraws that happen when the queue pops for CT are people doing this exact thing, people looking for people close to or on their drop chest to save their own time. The myth reward is also only at the end so there's that too. Just another way the loot lock-out just promotes bad behaviors.