Agreed. Back in the days when I used to smoke in customers' homes whilst painting, I would open a sliding sash window and some days I needed to blow the smoke out of the upper part and not the lower part because the lower part would blow back in. Depending on temperature/wind etc, the next day, I might need to use the gap at the bottom of the window.
In houses that only had a single top/outward opening sash, I soon learned that the left or right side of the opening would be either air in, or air out. By that I mean that same opening simultantaneous
With regards to heat pump driers in a shed, I thought that they weren't recommended for cold areas.