I really thought it up while I was EVing a P2 and told Wolfy :]
Gyarados does kinda wall him, well you could always run HP Fire which OHKO's Metagross with SR 93% of the time and does 75%~ to Jirachi I suppose...yeah but once the opponent figures out that it's mixed and doesn't have something that can hurt Gyarados they could use it as fodder I guess. Well it's not making the best of his SpAtk but 349 SpAtk + LO is still fairly decent.
It wasn't serious anyways, I'm not saying it's a great set either. It was just something I brought to see what he thought :P