Brock, Saw this a about a month ago. Made the chain and bungee ( need about 4" of 5/16" chain and short heavy bungee strap) set up like shown and it works as advertised- verified. Also you can use a tire screwed to a chopping log round and it keeps the wood from flying around as well.
Must be nice to split wood without knots! Don't think this'd work having to take full force swings on rounds of wood. This guy's lucky to have clear wood to split.
Didn't think of that.