So you can continue to log out even after you've been agro'd by someone.
Custom clients can automatically start the logout timer upon seeing an unkinned player and from what I'm told, the logout can only be aborted by hitting the person in melee. It's unlikely that you can actually close a 40 tile gap in time to cancel their logout so it's basically a get-out-of-jail-free card
https://youtu.be/vDUjvuOTsLo
So stupid