How accurately can aircraft predict the best altitude and route for their journey to take advantage of high altitude winds ?
How are winds aloft measured? With what frequency and resolution ? Is it trial and error, or reports from 'company' or is there a way of 'crowd sourcing' the information? If there was an automated system for all aircraft to continually share the windspeed and direction they were encountering, that should build-up a nice picture?
So many questions....