I retired on the L-1011 in 1987 from TWA. My recollection is that the CAT IIIB in thise days was no DH, but there was a minimum RVR to commence the approach. The figure was 750', I believe.
I flew JFK - Seattle-Portland and back for many years. I put it to use very regularly on those trips.
On touchdown, there was zero forward visibity on many occasions. As the nosewheel lowered to the deck, I could usually see some lights. The plane rolled right down the CL. All you had to do was remember to pop the spoilers, use the brakes, and reverse - being carefull not to get any assymetrical thrust.