Originally Posted by
oicur12.again
Lets make it simple:
You fly the approach a CAT I ILS where a NOTAM is in force increasing the min viz to 4000 (1200m), as was the case recently at a previous carriers destination. You reach the MDA and can see the approach lights and the decision bar and several rows beyond that. But you cannot see the runway threshold lights.
Do you land?
Is there a corresponding raise in the MDA as well? Typically a change in required vis goes hand in hand with a change in MDA or DA, in which case the amount of runway lighting you can see will probably be the same.