OK - he might be closer to outthinking himself than mastermind but I would take the opinion of a player who isn't worthy of playing abroad with a gigantic pinch of salt.
Still, this is kinda amusing. Maybe Gregg wanted to test the 2 striker thing out knowing we were through. Or maybe he didn't want to tip his hand regarding tactics for the knockouts.
Time will tell. Perhaps he is a true mastermind, one worthy of previous masterminds Arena (he of the indefatiguable nostrils) and Klinsmann (he of the indefatiguable optimism)(until he threw players under the bus).