I know most thru-hikers got north one-way (Springer to Katahdin). I'm also aware of the southbound strategy (Katahdin to Springer) and the basic flip-flopping strategy (Springer to WV/MD/PA area then fly/drive to Kathadin and head south the the point where you left the trail).

Has anyone ever tried some kind of unconventional flip-flopping on a thru-hike? Like start in the middle somewhere, go north to Katahdin, then either go back to either northbound or southbound the southern section you skipped over?