Quite a few Airbus operators deviate from AB procedures on this particular subject and let the captains only taxi.
Could it be that the most senior, influential and senile captains (often found in higher offices) find it too challenging to do different things on the outbound and the inbound leg, especially if flying only a few times a month?
Anyway, how much training does it take for the bright F/O to be able to taxi the little bird around once he moves over to the left seat?
Balance the risk/training value and pick your procedure......(F/O job satisfaction is a little bit like female orgasms...OK if not too much of a fuzz).