Yeshayahu HaKohen Hollander asked:
Could it not be that Rashi agrees that Seuda Shelishit DOES NOT require Pat, and the food of two meals we leave over referred to is only Hametz, but the third seuda is NOT hametz.
Shana Tova
Yeshayahu HaKohen Hollander
The Kollel replies:
Your suggestion would work well in the Gemara, but in RASHI it is very difficult to say that, because his words (DH Mazon) imply that the third Shabbos meal is similar to the first and second -- i.e. it is with bread.