I am not sure that it is pointless in these circumstances. The existence of a counter-example suggests that it cannot be taken as granted that what was presented in post #5 as an established fact ("Following a schedule change, BAH absorbs any difference in the hotel element if you rebook within a couple of weeks") is in fact as certain as was suggested in that post.
I do not think that there has been any trumping of the debate nor manifestation of DKYWIAism but rather useful additional context: if there was a discretionary element to the policy, you would a priori expect it to be exercised in the circumstances outlined by orbitmic. Again, this is useful information even if it is not conclusive (but neither does it seek to).