Hi,

Duplicated posts is a pain.

However here is my take on trying to work it out :

In a 20mph wind if you stop and sit there that is
clearly nothing like doing 20mph with no wind.

Rolling resistances at low speeds into the wind will
be much less than with higher speeds with the wind.

Still I can't get my head around why I can do 10mph
into a 20mph headwind, but only 25mph same tailwind.

(I will work it out eventually, physics is physics)

rgds, sreten.