"GuS wears a HAT" is a useful acronym to figure out a VDP. Take the Height Above Touchdown (HAT) divided by the Glideslope angle. HAT/GS = VDP
An easy example: We know that for a 3 degree glidepath we want 300 feet per mile. So, if we have a 600' HAT we would want a VDP of 2 miles from the end of the runway. 600/3 = 2 "GuS wears a HAT"
450' HAT would give a 1.5mile VDP from the end of the runway.
The DME may be different if not taken from the end of the runway.
