From the Boeing 737 QRH>
Ditching Final
LANDING GEAR lever. . . . . . . . . . . . . . UP and OFF
Flaps . . . . . . . . . . . . . . . . . . . . . ___, Green light
At 500 feet, advise the cabin crew that ditching is
imminent.
At 50 feet, advise the cabin crew to brace for
impact.
Maintain airspeed at VREF. Flare the airplane to
achieve the minimum rate of descent at touchdown.
Maintain 200-300 fpm rate of descent until the start
of the flare.
At flare, rotate smoothly to a touchdown attitude of
10-12°. Maintain airspeed and rate of descent with
thrust.
At touchdown, reduce thrust to idle.
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Note there is no mention of speed additives to account for headwind component or gust factor. If these additives are required for landing on dry land - why not on water?