Hasn't anyone ever attempted to land in fog but can see the runway all the way down the approach ?? It happened to us in Guernsey, RVR was 550m / 200m / 125m. We could see the runway and airport from about 10 miles out and stayed visual until about 100ft, the runway then disappeared. I know a few people this has happened to and is the reason that a 'visual' approach should not be carried out if the RVR is less than your required minima.