Before we start arguing about the semantics of llanfairpg refusal to orbit on final, let's all agree that this was a highly unusual request at a highly inconvenient time. I'm sure all of us have had one of those one way or another
Just to clarify or re-clarify I am refusing to do anything in any aircraft (public transport or private) which I, the commander, considers to endanger the aircraft, that is written in law and is my right. If the controller is this case had said, ' Go around', I would have considered that to be safe and correct although I may have added in this case, " confirm you are a licensed ATC controller?"
I had a similar event at Birmingham about 5 years ago where a controller asked me to go around in a medium jet transport while a similar aircraft on a test flight was told to line up. I filed an ASR as I thought the go-around was unessecarry and the controllers situational awareness to be extremely poor. I was later informed by the CAA in writing that the controller had been 'spoken to'!