GAW,
I am not sure how to interpret that Biur HaGRA and the quote from Avos D’Reb Nosson. Chibuk v’Nishuk is an issur d’oraisa (according to the Shulchan Aruch) from the posuk of “lo sikrivu” but dibur, even of kalus rosh and schok, is only assur m’drabbanan. But the Avos D’Reb Nosson cited by the GRA conflates them.
One of my main points in my original post on this subject, and where I thought the most contention would be, was that there is no heter of “l’toeles” for ??????? ????????? ?????. The “l’toeles” heter brought down in the Shulchan Aruch is specifically for histaklus.
Note: You haven’t answered my question about date-night with ishto nidda.