DFC,
Yes with regards to DA MDA....
DA and MDA are the same for IMCr or IR holders as we all know very well. I would feel comfortable taking the aeroplane down to minimums if I had too, as it is withing my personal experience envelope...
Had some pilots followed that then the population of Blackpool pilots would be 2 greather than it is today and also there would not have been the IMC CFIT in North Wales that killed one and ruined the life of another.
You could also say that perhaps they should have climbed higher into IMC and continued on instruments had they been able to?