How bad would it be to use a dog gear as a brake?

[aphelps231]

So in a completely hypothetical discussion, the idea of removing the inner coupling gear on a WCP DS gearbox and replacing it with a machined piece of aluminum that is fixed to the motor plate of the gearbox to bind with the dog gear to use as a brake came up. Of course, we wouldn't use this to stop the robot in motion, it would only be used once the robot has already stopped to prevent the wheels from spinning.

Is this an awful idea? What other successful methods for locking the wheels other than the obvious disc brake have you seen?