I have made a third submission - this time an amendment rather than a missing one - and we'll see what response is made by the GRO.
Bearing in mind that the GRO probably works on the same basis as others with customer service teams (ie as long as 80% / insert your own % here) of customer contact results in no further contact) that is the quality of service we have to accept. In the private sector (fuel companies, for instance) they will eventually offer you a "shut-up-and-go-away" minimal gratuity and, if that fails, challenge you to go to the relevant ombudsman, etc.
What they won't do, is change their processes.