Forgetting the excellent capabilities of VNAV for a moment and reverting to simpler days, is there a rule of thumb to further refine the FL x 3 rule for Top of Descent calculation, when there are excessive head or tailwinds? Like so many miles to be added/subtracted to the distance for every x number of headwind or tailwind knots?
This is assuming you want to stay on your standard descent speed profile and not alter it.