Who is John Gruden?

Last Friday Night was all about going to Chuck - E- Cheese with my kids. On the way home as we were talking, I told my daughter about sitting next to John Gruden at a traffic light a few weeks back.
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I told her: "I was at a stop light and John Gruden pulled up next to me in his BMW 650 Convertible. He was in the Left Turn Lane and I was going to go straight." "at least I am 99% positive it was John Gruden"
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My Daughter seemed very excited and Said: "Oh my gosh, you should have followed him to make sure!!"
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I said: "Well he was turning Left, and I was going straight, besides what would be the point of following him?"
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She said: " You could have made sure if it was him?.... Wait.... Who is John Gruden?"
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