I think overall Moyes has done a decent job in cups compared to the teams in a similar position to us.
In comparison i think there can be no denying that Moyes' record is terrible against top four teams away, because many teams below us have better records than we do.
I'd say he hasn't done a "bad" job in the FA Cup. That competition is completely dominated by the top five teams in England every single year, so winning it is a big ask.
However, his League Cup record is appalling. That'd be fine if he played a B team or something but he doesn't, we've just been proper crap in it. That said, we traditionally are.