There was a time when just about every team's holder for field goals and extra points was their starting QB. It was that way from the 30's until around 1979. The a starting QB got injured on a field goal and missed a couple of games. After that teams started using their backup QB as the holder and that lasted until a backup QB got injured and as it turned out the following week the starting QB got banged up later in the 4th quarter. So then by the 1990's the started having the punters doing the holding.
Parcells tried several players as holder in training camp and the kicker, Nick Folk, told Parcells he preferred Romo so Romo did the holding. It's also been noted that because of not just that muffed snap but because it happened on 8 other times during the season because the league had switched to special kicking balls that the time allotted to scuff up those balls was only 5 minutes and only 1 or 2 got scuffed and the rest were slick like every other new ball. Add in the rainy day and a wet slick ball, and the muff happened. After that season the league gave kicking balls the same time limit as the regular balls for scuffing. Parcells wasn't to blame for that anymore than blaming him for Witten not getting 10 more inches on the play before.\
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