Chess Opening Theory/1. e4/1...e5/2. d4/2...d6
This is an inferior way to enter a Philidor. This is refuted by dxe5 dxe5 Qxd8+ Kxd8 Bc4, with an uncomfortable endgame for black. Black would lose the right to castle, and White would have a lead in development. According to chess365, after 5.Bc4, white wins 42.1%, 32.5% end in a draw, and 25.1% end in a black victory.
Of course, White can always enter the main line Philidor with the lesser 3.Nf3.