What is the reference for 15% slope for obstacle clearance?
The ROC is based on segments.
Typical ROC values for en route procedure segments, 1000 feet (2000 over designated mountainous terrain);
for initial segments, 1000 feet;
and 500 feet for intermediate segments.
At the FAF, you have a ROC of 500 feet and it tapers to 200 feet minimum.
These ROC's are nothing along the lines of 15%, with FAS ROC being on the order of 1:40 to GPA.
I see little reason to D & D on the YPAD procedure, in fact I would persuade against this, knowing how the database for man-made obstacles is managed worldwide.