An act's obligatory minimum and a supplementary act that perfects worship are distinct legal categories. If repetition is recommended as completion in a particular setting, that does not mean the obligatory minimum has been increased.
Likewise, the number and place of bowings or prostrations within prayer are determined by the governing rules of that prayer, not by a general preference for more worship. In discussing washing, the minimum required act and any recommended repetition must remain distinct.
This distinction clarifies the juristic status of the proposed attribute, which is exactly what a denial-of-attribute objection demands.