FFXI didn't have an auto disconnect, but it wasn't a problem because the population was generally pretty small, and players had bazaars, so they needed to remain online and AFK in order to make a profit. --Toya on Shiva, I'm looking at you, all AFK in the Bastok Markets for 10 years!!!!!--
But this games doesn't have bazaars like XI did, and the population I'm going to wildly and inaccurately speculate is twice what XI had, so there's no reason in the world to stay logged in unless you think your character is alive and will have an existential crisis if it finds out it can blink in and out of existence.
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Star Swirl on Behemoth AKA Best-hemoth AKA The Cool Kid's Table----60AST, 60WHM, 60SCH/SMN, 60BLM, 60MNK, 38 PLD, 34DRG, 31NIN, 27MRD
FFXI- Derpypony on Asura
Check out the Dream Network, a Twitch.tv community for XIV fans, featuring notable streamers like Mr. Happy, MTQcapture, Rahhzay, and Slyakagreyfox! http://dreamnetwork.tv/forum/index.php
Then maybe check out myself, EquestriaGuy, on twitch at http://www.twitch.tv/equestriaguy