There can be many unexpected circumstances that could pull you away from your computer for 30 minutes or more, making this timer ridiculously short. Login issues mostly went away after the last big maintenance, so why did they still feel the need to put this in? People aren't really staying logged in just to keep a spot on the server anymore, because it hasn't been necessary.

Please, remove this needless feature once the worlds are stable , or make it on by default but optional in the configuration. If you don't, people are going to make keyboard macros and stuff to circumvent it, so it's pointless anyway.