As PP mentioned, the ferries and boats to the Bay Lake resorts are free floating, and they shut them down in bad weather like high winds (which we experienced back in March).
Yep, free floating. We have seen the ferry come over to the Poly dock now and then. Always empty and it appears that they are training a new skipper in fine control of the ferry with several 'dockings' at the end of the Poly pier.
Perhaps the confusion is between the ferries on Seven Seas Lagoon which are not on tracks and the Mark Twain on the Rivers of America in the MK which is on tracks.