re: soap and nolad

Question

Please see the Rama on Siman 326 Se'if 10, and the Mishna Berura. Also, you will notice the same Din with regard to congealed liquids, which the Mechaber holds can be heated back up on Shabbat, but the Rama quickly adds in that one should be machmir, and the Mishna Berura explains that he is referring to an issur nolad (Siman 318 Se'if 16). The nolad is in the fact that there is a transition from solid to liquid, so it would not apply to liquid soap. I have been told that this is why my Rosh Yeshiva, Rabbi Chait, holds that bar soap is a problem. What do you think? --Aron