In fact, the whole notion of consulting ones confessor for instructions in frequency of marital sexual acts is revolting.
At first glance your comments seem reasonable. Then the questions. Are you suggesting my consultation with my confessor and my wifes with hers, regarding our use of NFP (that would be specifically "instructions in frequency of marital sexual acts", as that is intrinsic to NFP) is revolting? Are you suggesting that sex is not a subject for the confessional?
Asking a celibate priest about sex is like asking a vegetarian about proper portion size for filet mignon.
There is no reason for married people to discuss the frequency of their perfectly legitimate and moral sexual acts with their confessor.
Discussion of NFP is only required if one wishes to avoid one's duty to society by having fewer children than is justly required of all. In that case, the discussion should be about the reasons why one is doing so ("medical, eugenic, economic and social" in Pius XII's list), and not about the sexual acts to be used or their frequency.
Pius XII's Allocution specifically says to the Midwives: "It is your function, not the priest's, to instruct the married couple through private consultation or serious publications on the biological and technical aspect of the theory, without however allowing yourselves to be drawn into an unjust and unbecoming propaganda."
Sexual acts about which there is no moral issue are not a topic for the confessional and should be completely excluded from the discussion in the interests of the holy purity of the Priest-Confessor.