I'm surprised I haven't noticed this before. I was drawing up some letters and noticed letters like Z/N don't really follow the nib angle. So I got my PP out and wrote it just to be sure and sure enough the diagonal in /Z has little weight on the diagonal based on the nib angle and the stroke weight on /N has far more weight than lets say comparing to T's arm. It's as if the nib angle needs to change to accomodate that stroke weight. Pretty sure the change in nib angle is to compensate for weight but is this how roman letters were designed where nib angles changed between letters?