In general, most restaurants do not serve risotto, they serve a bastardised version of it. They cook the risotto well before service and keep it in the fridge for 6-8 hours. The reason is that it would be logistically impossible to serve traditionally made risotto in a busy restaurant.
The method I have given is the way I cook risotto both at the restaurant and at home. Personally, in my view, there is very little difference to the end result (sorry risotto gurus) and my method is easier for the cook to serve.