Fish Serving Fork

what is the correct technique for filleting cooked dover sole in a restaurant?
I am training my staff in a four star hotel the correct way to fillet and serve dover sole in front of guests but am struggling to find a description of how to do it. I know that some people like to use two Fish Knives whilst other people like to use a fork and knife but that is about as much as I have managed to find out!
Both techniques are deemed to be acceptable. I have found that it rests with the comfort level of the server. I personally prefer knife and fork. I have tried the two knife method and can’t seem to get the hang of it.