Centaurus
Certainly in the days of tail-draggers 1.1 Vs ensured the lowest touchdown speed in the three-point attitude. This allowed for full and immediate application of brakes. The P-charts back then were fairly sketchy until DCA addressed the problem by publishing a Flight Manual that took precedence over the manufacturers handbook.
It seems that modern flight manuals and more specifically landing P-charts specify a Vref/Vapp/TTS of 1.3 Vs and I don’t see that instructors are in a position to advocate otherwise. But having said that, such speed is normally attained at fifty feet above the landing surface and some five or six hundred feet short of the touch-down point.
The Cessna 208 manual for instance states:
"After all approach obstacles are cleared, reduce power to idle. Maintain 78 KIAS approach speed by lowering the nose of the airplane. Touchdown should be made with the power lever at IDLE and on the main wheels first. Immediately after touchdown, lower the nose gear, reposition the power lever against the spring in BETA range, and apply heavy braking as required."
The airspeed for emergency operation is specified “Precautionary Landing (Engine Power / Flaps Down) … 80KIAS”. The manual specifies Vso at 50 KIAS!
Since the approach speed is determined having due regard to possible turbulence or engine failure, operation at a lower speed would be outside the manufacturers instructions. Should we be training students otherwise? Would the consequences of taking out a barb wire fence at the end of a paddock be worse than loss of control on short finals?