I still dont understand the 757 Cat3 problem.
Britannia used to land in Cat3C conditions.
From memory, I heard the first ever Cat3 landing with Britannia.
RVR was 75m and tailwind component 3kt.
The pilot when departing to TFS told ATC that on his return, the above conditions were ok as long as the tailwind did not exceed 3kt.
So, what has changed?