BandB, let's assume you and I are not marina operators or dock masters collecting rent, by the foot.
Please understand, I am not being critical nor criticizing you at all.... I for one and maybe others are seeking the final and exact definitions and location of each measurement.
I will admit, I have never heard the term of "deck length" until you mentioned it.
So now, please identify the various lengths from the WL (the lowest point of the boot top) upward, excluding any bulbous underwater protrusion. We can discuss that after we all define the other measurements.
Permit me to start with a question. Does the water line length, WLL, include or exclude the swim platform if the swim platform drags in the water when the boat is underway?
May I suggest, the "beam" is defined as the maximum width aka navigational beam. (Submarines had two definitions of 'beams'. The maximum width of the pressure hull containing livable space of the submarine, and the navigational beam, the outer skin of the hull. The part that hits first. SMIRK
I think we are all guilty of using terms without an exact definition.