melacha creative work - Non-Yemenites who heat up soup after the start of Shabbat?

The most widely held practice regarding heating up liquids on Shabbat is that it is prohibited, though there are differences of practice between Ashkenazim and Sephardim regarding sauces and such (Sephardim are generally more permissive).

There are Yemenite Jews who practice strictly according to the Rambam's rulings and therefore they will lechatchila, a priori, (i.e. it is 100% permissible) remove cold soup from a refrigerator and place it on a hot plate for heating purposes. For an interesting shiur on the subject from Rav Melamed, rabbi of the Har Bracha yeshiva, see: http://www.yeshiva.org.il/midrash/shiur.asp?id=642

My question is the following: I was told by an old friend of Atara Twersky, the daughter of Rav Soloveitchik, that she also used to heat up soups on Shabbat. I don't know if this means that she was following the practice of her father, or her husband, the Talner Rebbe, Rabbi Isador Yitzchak Twersky.

Does anyone have any knowledge of Rav Soloveitchik's halachic rulings in this area? Are there others who follow this practice?

Answer

I have heard, I believe from Rabbi Daniel Stein, that Rav Soloveitchk is quoted as crafting the following logic:

1. 
   

   Chicken soup, unlike water, does not as a practical reality lose its cooking (azil lei bishulei) when cooled. If I have water, boil it, and let it cool, it is basically back to where I started. If I cook soup, and let it cool, I have cold soup, not the ingredients for soup again. Having been cooked once means that it is a new thing. As such, there is no cooking after cooking for soup. This is based on the Eglei Tal.

   
   


2. 
   

   The prohibition to put soup on a blech/plata on Shabbat day is based on cooking, not an independent prohibition on returning/resting anew. This is based on the Biurei HaGra.

   
   


3. 
   

   The Ran is lenient on returning even cold refridgerated foods to the blech if they were on the blech when Shabbat began.

   
   
   

By putting these together, one can reheat a soup on Shabbat day that was on the blech Fri night. This was quoted (to me) mostly as a demonstration of the cleverness involved and definitely not as halacha l'maaseh.