Good post brummybloke.
I get this, and I agree with you that longer term we'd hope Guilbert is good enough to do what you say. However, it very much seems like Dean thinks he's not the answer currently. If he was, he'd play.
I think we have more problems elsewhere than full backs though. I think people would want to change full backs because they wanted the other guys to start in the first place. And now that we have lost two, it's natural to want to change this to the way people wanted all along.