If you have been in icing conditions for an extended period of time, and at 50ft you fly below Vref, you will drop like stone. The stalling caractristics are based on a clean wing. The 1.30 and (1.23 in fly by wire airplanes) stalling margins will not protect you. I am of the opinion to fly at Vref + all the corrections(wind and gust) and bleed the speed off during the flare and touch down at Vref +the gust factor.
The advantage of reducing the landing distance, by flying below Vref is outweight by the chances of tail strike and reducing the climb performence in case of abort landing.