the position you keep arguing is that -- in the specific situation when a defender catches a pass for an interception and a receiver is right there to try to stop him from making the interception -- if the receiver tries to take the ball away from the defender at any point after the interception has been made, all he has to do is keep one hand on the ball while they go to the ground and it is a simultaneous catch.

there is no point where tate has CLEAR possession of the ball but there are several points where jennings does. in the last frame of the picture above the ball is clearly against jennings' body and tate is underneath him. not only that, but tate's right arm is ON JENNINGS and not the ball. i can think of no ruling ever in the history of the NFL where this was considered a simultaneous possession until monday night.