Originally Posted by joejack951

Ha! I posted that having just woken up and clearly didn't proofread. The requirement is for the threads to end no more than 16mm above the headtube so whether the correct math is 5 or 9mm, you are still good to go

What the <16mm above the headtube is ensuring is the upper race can screw down the steerer tube far enough to contact the upper bearing. The <45mm above the headtube ensures that the steerer tube doesn't bottom out internally inside of the quill/upper race portion. I could only accommodate a certain amount of steerer tube inside of that area before I start infringing on how short the unit could be trimmed for those wanting to run slammed stems with short-ish steerer clamp areas.