It depends on the weather. It depends on the rwy lenght. It depends on the ac weight. It depends on the ac type. It depends on the ap elevation. It depends on your experience. It depends on your fatigue level. It depends...
I appreciate the advice given by the testpilots, as 777something said, Mr Boeing, Airbus , etc, has done hours and hours of flighttesting. The airlines on the other hand, are operating these aircraft for thousands of hours.
Strictly following your AOM is as wrong as disregarding it.
I will add 40 kts to Vref if the conditions and rwy lenght so dictates. Its not in the book, but its my decision. Im am paid to think.
Same time, landing at 15 kts overspeed every time, just to do a smooooth touchdown, is just poor airmanship.
You are not wrong. You are doing what the book says, and what you have been taught. More important, what you are doing is not unsafe.
You will be burnt below 30 ft sooner or later, but it will only bruise you pride. Next time into the same airport, on the same rwy, you will maybe keep the thrust on a bit longer. Because it feels right.
Happy landings!