What a load of crap, if a professional pilot is really saying they landed hard as they were told to flare at 20ft instead of 30ft regardless of the actual dynamics of the landing then we are in trouble. Yes the SOP technique may be to flare at a given height but clearly this relies on how the approach has shaped up, you don’t just leave the flare if your ROD is high and say ‘but the book tells me I can’t do it above 20ft.’