Sure, possibly. But you've, I assume, inadvertently chosen the team with the most year-to-year turnover in defensive players. It's easy to see your list and just chalk it up to randomness, but I'm simply saying "not so fast, my friend".
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Shouldn't we study something before we give up on it?
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That being said, 'turnovers' is too vague. There's fumbles and interceptions. Those could (and should, but aren't) be further broken down into forced fumbles (on a tackle), unforced fumbles (guy just goofs the ball out of his own hands), tipped INTs, wayward throw INTs, miscommunication-on-the-route INTs, and then traditional INTs.
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If we had those stats handy and have for decades that we bandied about, then the turnovers idea becomes a lot less likely to be random. Or if it was random, we'd know. But we simply don't have the stats breakdown like we do for yards and points and completion %, etc.
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If early fans and stat-keepers were obsessed with turnovers from the start, we'd have a handle on it.