"For the BEGINNER, these are paramount directions, as you know, for BASIC rotation in Waltz...and of course, the "amount " of turn would be explained."
That was neither the question nor the criticism. Knowing the default alignments is useful, but it is not the answer to the question that was asked.
"His Q seemed to imply that he was unsure on WHICH foot to commence and in what direction"
That was not the question at all. The question was "How should the man lead the reverse turn so that the women is not confuse it for a left turn that is part of a box?" This was later clarified to being how to lead a 3/8 turn reverse vs. a 1/4 turn one.
As you know, both commence with the same foot, and quite possibly in the same alignment.