it seems to me that when using the CDFA procedure. you are not flying the 3.0 angle down to the MAPt, at the MDA. you are flying the angle down to the Threshold. this will put you in a straight line down to the runway when you hit your MDA/DA, however, you will not be anywhere near the MAPt when you hit that target altitude. it seems to be the equivalent of shooting an ILS(with no G/S reference) but making your DH higher as if you were circling. instead of going missed at Station passage, time, or a given fix, you go missed at the MDA/DH. this makes every approach basically the same. you fly the prescribed decent rate based on the angle for the approach and your groundspeed.