The body doesn't matter for how many shots it takes 2 hit KO it. As you've observed, nothing's reduced enough via the body to block 2 hit KOs. That's not what the Body's intended to do. It matters for decks such as Lucario, Magmortar, Empoleon, and Ampharos decks, that want damage spread around in order to be most effective. Lucario's snipe for 20 to the bench? That's 10 off while your turn starts, and 10 off while your opponent's turn starts. They just did nothing to the benched Ludicolo. If your bench is only Ludicolos then this is an amazing advantage (if you have anything else such as Lotad or Mantine, they have a viable snipe target, and you've just lost your advantage).
Attack is easy to pull off since we still have Scott in the format. DP on will see Ludicolo lose a LOT of power (unless we get something to search out stadiums), but in the meantime, it's plenty viable.
That is why it has potential. Best deck in the format? Likely not. Capable of countering some decks in the format? Very easilly. Capable of countering most decks in the format? That's questionable. It fails against Kricketune, Bannette, Blissey, etc. for instance. (you're even on prize exchange against Krickets, and will need some way to load energies onto the Ludis to come ahead. Don't say Blastoise, as this clogs the deck up.)