bracha on besamim on Y"K which falls on motzei shabbos; bracha on ner when a woman recites havdalah

There is a machlokes ha'poskim whether the bracha on besamim is said in havdalah when Y"K falls on Shabbos. The SA writes (624:3) writes that the bracha is omitted, as the purpose of besamim is to help us recover from the loss of our neshoma yesira, but on Y"K there is no neshama yseira since we can't eat or drink.  The Mordechai disagrees.  Taz quotes Maharashal who argues that there is no downside to being choshesh for the Mordechai and adding the bracha, as the bracha is a birchas ha'nehenin.  If you smell the spices and enjoy the fragrance, it's not a bracha levatala.  This is how the Mishna Berura paskens l'maaseh:

אבל רבים מהאחרונים חולקין ע"ז וסוברין דכשחל בשבת יש לברך על הבשמים ואין כאן חשש ברכה לבטלה כיון שנהנה. ומ"מ אין להורות לצבור כן ולמחות בידם במקום שנהגו בבהכ"נ שלא לברך על הבשמים רק לעצמו בביתו יכול לברך [פמ"ג].

Aside from the issue of bracha levatala, Taz raises a different concern.  If one is not obligated to say it, wouldn't adding the bracha on besamim constitute a hefsek between the bracha on the kos and the bracha of havdalah?  He draws an interesting analogy to tekiyas shofas to get out of this problem:

וויש לכאורה לדחות זה שכ' מאחר שנהנה כו' דמ"מ יש כאן הפסק בין ברכת בורא פרי הגפן לברכת המבדיל בבשמים אם אין הכרח להם מ"מ נראה דעדיף טפי לצאת ידי כל הדיעות מלחוש להפסק וראיה מדברי ת"ה סימן קמ"ב לענין קשר"ק שתוקעין בסדרים דבזה נפיק ידי כל הקולות דהיינו או קר"ק או קש"ק ולא חיישינן להפסיק אם קש"ק עיקר הוה התרועה הפסק ואם קר"ק עיקר הוה השברים הפסק דכיון דעכ"פ כבר יצא י"ח לא חיישינן להפסק  אע"ג דעיקר התקיעות הם על סדר הברכות הכי נמי  כיון דיוצא ממ"נ לא חיישינן להפסק:

I think the simplest solution to be yotzei both deyos here is that of the Chayei Adam (klal 145.  My son pointed out to me that R' Ovadya says the same in Chazon Ovadya.):

והרוצה לעשות מן המובחר לצאת דעת האומרים לברך גם על הבשמים כשחל בשבת נ"ל דלאחר שסיים ברכת המבדיל בין קדש לחול אז יברך על הבשמים ולא באמצע הבדלה

This Taz has ramifications not just when Y"K falls on Shabbos, but for other havdalah issues as well.  The Biur Halacha at the end of OC 296 is medayek from the MG"A that women are exempt from the birchas ha'ner when reciting havdalah on motzei Shabbos.  Had you asked me, I would have said based on this Taz that if they have no chiyuv recite the birchas ha'ner, they should not be allowed to recite the bracha, as it would constitute a hefsek.  This is in fact how R' Tukashinski paskens in his luach.  

The sefer Halichos Beisa (end of ch 15) disagrees.  He suggests that even according to the Biur Halacha, women may recite the bracha if they desire to do so.  The difference between this case and that of the Taz is that when it comes to a regular motzei Shabbos, the fact that women lack a chovas ha'gavra (odd to use that term here : ) to say the bracha does not change the fact that it is part of the takanah of what constitutes the normal seder of havdalah.  On Y"K which falls on Shabbos, however, since according to the SA since there is no neshoma yseira, the bracha of besamim is not part of the "cheftza" of the takanah of havdalah for that day.  

As proof to this argument he cites the PM"G that an aveil is exempt from reciting the bracha on besamim since he is too upset to have the enjoyment of a neshama yseira; however, the PM"G implies that if the aveil may recite the bracha if he chooses to do so.  Here too, the aveil may lack a chovas hagavra because of his circumstance, but the takana of havdalah on motzei Shabbos includes the bracha, and therefore there is no issur to say it.

Important to note that this issue is only with respect to a regular motzei Shabbos. The Halichos Beisa suggests that when Y"K falls on Shabbos even according to the M"B women are obligated in the birchas ha'ner, as the purpose of the ner on motzei Y"K is part of havdalah -- to distinguish between the ner that we were not allowed to use for 24 hours and ner that we now can use -- as opposed to on a regular motzei Shabbos where it is a shevach for the creation of candlelight.