If Mustard had've ripped up the ODIs Graveney may've had a case, but he was pretty ordinary. His selection was pretty left-field in the first place, I don't actually recall anyone mentioning him even as a possible for the ODI leg beforehand, so his rention is a wee bit baffling IMHO.
Well Beevs did, but he'd tell us Gordon Muchall should play for England, so he doesn't really count. AND NO, THAT'S NOT A "DIG" AT HIM!!!!!!!!!!!!!!!!!!!!!! So don't anyone start on that.
Mustard's ODI selection was fairly typical "one-season selection" sort of stuff, really - Mustard had been crap for years, had 1 decent season, was "an aggressive opener", and given the current fascination with having an aggressive wicketkeeper-opener, he was straight in there.
I agree that it didn't make any sense whatsoever to pick Mustard for the Tests and I said so at the time. But at least the decision now appears in somewhat more clarity than had originally seemed the case; we now know that no-one in-committee
actually believes he's a better First-Class batsman than James Foster, which is something at least. But the fact that he was retained for the New Zealand leg ahead of Foster still baffles, and we can only assume the situation is the same as in SL.
If I was told that Prior was to be gone for this leg, I'd have gone for Foster and Ambrose, every time. With the former the first-choice.