There's your mistake; stats misrepresent what actually happened. In each game Dak shut down early, then padded his stats against loose defenses after the game was out of reach. In 2016 the Packers got a little careless at the end, allowing the Cowboys to actually take the lead, but they easily took back the lead and won the game.
Stats lie. They don't show what actually happens in a game. They don't show how a team trying to comeback exhausts themselves physically, and just as important - emotionally.
So when the Cowboys repeatedly fall behind because Dak chokes in the first half, the opposing teams can play loose and let the Cowboys exhaust themselves and the clock, but they are always in control.
In seasonal games it's the same, with Dak padding his stats against the woeful NFC East and other weak teams. But each time the Cowboys have to face an opponent that is a winner, Dak chokes and the Cowboys lose.
Who can forget losing the East to the Eagles, when for weeks the Cowboys needed only one win to clinch it. Losses to the Vikings, Bears, Bills, and then an injury riddled Eagles team ensured the end of Jason Garrett.
But Jerry should have sent Dak with him.