not recommended..
Well, you may select it at your own risk. Airbus doesn't talk about it at all, as far as my knowledge goes.
Unlike the turboprops, where it is a usual practice, I think it is not a wise idea to do it on A320, especially on taxiways where danger of FOD is higher than on the rwys..
I would do it on taxiways only in case of brake failure..
cheers