So, if the actual visibility is CAT 3 it is considered that you cannot have sufficient visual clues so you must go around with a warning below DH, according to JAR OPS?
the problem is... How do you know what the visibility exactly is?
(Please don't make me count center line lights in that moment...)
Therefore, unless it is specifically forbidden to go around with a warning below DH, wether in SOPs or in JAR or wherever, it remains a Captain's decision to continue or go around depending on his assessing the visual cues as sufficient or not.
If conditions are actual CAT3, I think we won't have sufficent visual cues for a flare and landing. And many times we won't even know why the autoland is not reliable so we don't know if we are over the threshold or what. If conditions happen to be better, we can see well and land.
However, if warning is due the LOC transmitter failure, visual cues might happen to be sufficient to flare and land on the TDZ, but not sufficient for the subsequent roll out. But this could also happen during the roll out itself after a non event autoland!
Argh!
I have come to the conclusion that I don't like CAT III