Very interesting thread, but I can't help thinking that adding increments to MDA has been borne about by the ability to do it through automation. Non-Precision 3 degree approaches are not realy that new, I have flown many in older electro-mechanical instrument transport A/C. We never added 50ft to our MDA by moving the little plastic bugs up a bit. I now fly a very mordern A/C (have done for a bit now) and have noticed the only thing that has realy changed is an unhealthy faith in the autopilot system.
If the CAA are so concerned that the British pilot community are busting MDA during the go-around, presumably they will go into print over it, or is this an indivual Ops inspector thing ? MDA is MDA, MIMIMUM.
Ok, I can see the logic it even comes down on the side of caution and thats never a bad thing. However I think flying down to minimums (NPA), on a very dark and dirty night in an airliner, even if its 50ft above MDA is a fairly unwise thing to do, its somthing I would not do unless my life depended on it anyway.
Best regds