BOAC...from my discussion with the senior technical people at Boeing, the intent was to bring VNAV down TO a DH because of the accuracy of the system. The philosophy was referred to as "flying to near ILS limits using VNAV and GPS/LNAV/LOC overlays."
In absence of an integrated/automated VNAV system (AFDS) but using FPA or VS, it would be more correct to use the Derived Decision Height.
Would I bust a candidate for not using a DDH on a VNAV approach? It depends on the training philosophy of the company. What were the standards of training? There are many factors to consider. It would be a good debrief item for sure.