The Talmud continues to raise a difficulty. If they are so close in size, then it is still possible for him to measure them exactly. And if so, there again is a difficulty on R. Huna. If when the valid part is exactly the same as the invalid part the sukkah is valid, then the same would be true for a case where the open part was the same as the closed part. It too would be valid.
R. Ammi says that the mishnah refers to a case where the valid skhakh is actually greater than the invalid poles. If they are the same, the sukkah is indeed invalid.
Rava offers a different explanation. Such a sukkah could be valid if the valid and invalid skhakh were equal but placed in different directions.
Today’s section continues to explain the next line of the mishnah—why one can’t use the long boards of a bed as skhakh.
The Talmud begins by suggesting that our mishnah supports a statement made by R. Ammi b. Tavyomi that one cannot use discarded vessels as skhakh. Later we shall see that these are worn out pieces of clothing (which are called vessels in rabbinic Hebrew). Once these pieces of cloth are smaller than three handbreadths squared, they are no longer susceptible to impurity. Nevertheless, R. Ammi holds that they may not be used as skhakh. So too, our mishnah might refer to bed boards which have worn out and are no longer susceptible to impurity. Despite the fact that they are not susceptible to impurity, they may not be used as skhkakh.
The Talmud now rejects the support of R. Ammi from our mishnah.
Elsewhere (we shall see the context below) R. Hanan explained in the name of Rabbi [Judah Hanasi] that a mishnah referred to the long or short board with two short legs attached. The long and short board are the sides of a bed—either the long side of the bed with one leg from the head and one leg from the foot or the short side of the bed with two legs from the head or two legs from the foot. Such a long (or short) board is still susceptible to impurity (to be explained below). So too in the context of skhakh we are talking about the long board with two legs attached which is still susceptible to impurity and therefore cannot be used as skhakh. The implication is that if the long board did not have the legs attached it would not susceptible to impurity, and it could be used as skhakh. This would mean that the mishnah does not support R. Ammi b. Tovyami—worn out vessels that are no longer usable can be used for skhakh.