Oh I know. I was just trying to make the point of things being non-linear, AND, the non-linearlessnesses are unequal. It's complicated, and I don't have the answer. But I know your fundamental question of same power in each direction, does it feel the same? I guess it should, because power output should take into account everything. But does it feel the same, if same human output, but one way wind in face and other way wind at back? I don't know. I've been wrong enough to not assume until I can math it out somehow.