he should make clear that the mortises must be cut before the tenon shoulders and the groovers are milled, which i assume is indeed the case... i don't believe he says one way or the other... thx. t.
Agreed, although he used to post here often, and I believe he said it in one of his many helpful posts. BTW, if you'd use the same technique if you're using a pair of complementary-profile router bits, like what you might use for cabinet doors.
Enjoy your Domino!