Rule 6-1-2-c-1: Each Team A player, except the holder and kicker of a place kick, must
be behind the ball.
Though it sounds weird, according to this, the play is legal. I don't think you could justify a formation foul since there are at least 4 on either side of the ball when it is kicked. This is what happens when a coach studies the rule book, or one of his buddies is an official and has clued him in on it.
