Correct me if I'm wrong but winds aloft are always quoted in true, the only winds quoted in magnetic are runway surface winds?
Now this is my point, on a nav leg we fly magnetic and calculate drift from our winds aloft which are in true. Never in my training have I been told to +/- variation on the winds aloft or was I just asleep at that point? Has anyone else noticed this or is it negligible in the UK where variation is 4-6o, where I fly anyway.