So they've got 2 seconds or less to get their act together in the flare right?
Yes that is quite possible.....but they will have a fair idea of what drift trend to expect if they are taught situational awareness.
Time is an interesting subject when examined in the learning to fly context...two seconds can be forever sometimes...
Any value whatsoever in upper air-work? If not why not?
Yes upper air-work will teach them control inputs and rate of change for each input.
However the art of directional control during the approach and landing is best taught actually doing it in various wind conditions.