BelArgUSA
We did a lot of CAT IIIb landings at Delhi (VIDP) airport during fog season, and many a times RVR was 75/75/75. There were occasions when an aircraft would land and was unable to find their way. Many a times they'd request follow me to come to the runway so they could vacate the runway.
In my previous two companies in India we were Cat IIIb and we required NO DH and RVR 75/75/75. Any time the rvr dropped below 75 M the airport would essentially shut down. For take off we required a minimum of 125 M.