Here's another answer - a talkgroup CAN (but not always does) "follow" a mobile unit as it crosses the state. Note many counties have "travel" TGs on MOSWIN. This allows for example a deputy from Adair County way in the NE corner of the state to talk back to his dispatcher while he is at the Lake of the Ozarks or in KC. When he keys his mike at the lake, his radio "affiliates" with the local MOSWIN repeater/tower there, which realizes he is using the Adair Travel Talkgroup and sends the audio thru the system to the tower in Adair county. It probably goes over the Internet, could be phone lines, or could be microwave -whatever the towers are connected to. SImplification but the power of Affiliation is what makes MOSWIN a system and not just repeaters here and there.