Klecko explained this in Jim Kelly's "A Football Life". He said Kelly was just talking all game and said something to Klecko he didn't like. There was another penalty right before that that moved the ball to the 1 yard line. Red Cashion the ref called the penalty and Klecko said "Red, how can you call that?" And Kelly looked at Klecko and said "oh, first name basis, huh?" And that was when Klecko thought "what a good time for 15 yard penalty. They're only gonna move the ball 6 inches" since they were already at the 1 yard line. To be fair, Kelly was a prick when he played. Not necessarily justifying that play. Just explaining it from how Klecko explained it