I hate it too. There is a place for the prevent defense, but it is when you are up big, on defense, and trying to make the offense take time on the clock while trying to score. That means that you protect the sidelines so that all tackles happen in front of you and in the field of play to keep the clock running.
I could also see it in a situation where you are up 4 or so, but it's like 31-27 or something where the opponent has been moving the ball and scoring on your normal defensive scheme. Maybe then you try the bend but don't break style.
But when you've completely stifled them the entire game? Why change? Make them prove they can beat you. if they break one, then so be it.