http://www.ruhr-uni-bochum.de/bauko/downloads/bauko_geneigte%20daecher.pdf

Check out the drawing on page twelve. Would that not be considered a type of queen post construction? If yes, then those queens are clearly under tension. So to simply say king equals tension and queen equals compression would not be correct.
I am not sure why it matters so much what the posts are called anyway. As long as the structure can support itself....