I have a question regarding mid span purlin plates which are used in timber frames with common rafter roofs.

Some designs use vertical posts/plates and other designs use canted posts with plates that are perpendicular to the roof pitch. I like the way that the rafters connect to the canted plate but I prefer vertical posts that go from the floor to the mid span plates.

Is it possible to use vertical posts with a canted plate? OK, it's possible, but is it a good or bad idea and why?