Honestly, a "B" would have made the most sense, because it ended up being mostly a bomber, with a very limited self defense air-to-air capability. But yes, it does go back to the TFX roots. The F-111B was supposed to be the Navy version to do fleet defense, but it was just too damn big and heavy for carrier ops. They did actually launch one off a carrier somewhere along the way. They never bought the B models...ended up getting the F-14's instead.