You cannot argue with his success.
What success? Discounting the tenure of Jimmy Johnson, who succeeded only due to the most lopsided trade in NFL history, what success has Jerry Jones met? Okay, fine, a shiny new stadium... but not much else.
The fact that we're even talking about the success of Jerry Jones speaks volumes about just how much control he exercises over the team. Contrast him with Robert Kraft and Wayne Huizenga, who are totally hands-off when it comes to football operations.
He made a good decision to hire his college teammate, that much I give him credit for.