I have to say that as a pro BA guy this incident comes as a shock.
It shouldn't, and I'll tell you why.
First off, I've flown with BA First Officers that were secconded to the airline where I was at the time, so...I know the mind set.
Reasonable pilots all, good handling skills, pleasant folks.
Rather good decision makers, as well.
However....this absolute nonsence of having 'roll reversals' that BA espouse, is cr*p.
Note that this flight was a First Officer leg.
So far, so good.
However, with the nonsensical 'roll reversal' cr*p that BA uses, the First Officer is to taxi the airplane, the Commander then does...co-pilot duties.
Bad form.
To keep operations reasonable, the duties on the FD need to be
standardized, and 'roll reversal' simply does
not cut the mustard, in this respect.
I suspect...you can expect a few more of these BA fiascos, due largely for the reasons I have indicated, above.
In short, BA needs to reevaluate their FD procedures.
Urgently.
This very serious incident is just a case in point.