The problem is with exbal and not the method.
That's right on. Theoretically I'd say the 1 mph method would be easier to do quickly in your head but, unfortunately, Exbal doesn't cooperate.
I already thought about the 100 mph thing but Exbal limits you to 60 mph. I guess they figure we won't be shooting if the wind gets over 60 mph.
I think I'd personally like to use the 1 mph method for the ease of doing it in my head quickly but I can't stand the inaccuracy of it so it looks like it's 10 mph and some quick math.;)