The intent was to replace all instances of "masking" with "duct" since masking tape does not stick well to pavement. Obviously, we missed several "maskings." That will be corrected in a mid-year update.
My calibration courses usually go from one fixed landmark to another fixed landmark (such as a pavement expansion joint or the edge of a storm drain), and are not an even 300m or 1000ft in length. In that case you always have a partial tape length. It also means I always have a separate set of duct tapes for the second measurement.