Citation:
You could be doing 160 kts on final or 180 kts in a circling , you are still in C category as long as your Vref is within 121 -140 kts at threshold.
You obviously don't have a handle on the situation.
My "clueless" airline was TWA, that owned some 50 727s and had a very close relationship with Boeing.
I believe it was the way the airplane was certified but I am not sure of that. What I am sure of is TWA's prescribed speed for the 727's CTL procedure fell into Category D, at least at, or near, max landing weight.