Originally Posted by
FullWings
It does make me wonder, in the situation that the OP describes, if the PAPIs had been U/S, would his approach and landing been commented upon adversely?
Possibly not - but once you are in 4 reds on the VASI then there are no more clues if you get any lower.
Due to different wheel to eye heights on different types, there will always be a mismatch between ILS glide slope indications and VASI indications when very close to the runway - but you should never see 4 reds without comment.