Good to see Telecom is talking to British Telecom and taking the idea of a voluntary wholesale/retail split seriously. That would be a good outcome – for Telecom as much as the country.
One of the benefits of a split, is that much of the regulation would then be unnecessary as the wholesaler would be treating all retailers equally. Vertically integrated monopolies are inevitably regulated. Without the vertical integration then the only regulatory role you should need is a very light handed eye on pricing.