Shalom,
The gemara asks a stira in R' Yehuda from the beis hamikdash (see Tosfos). the gemara is mashma that the kasha is only on the 3 rd terutz that is mechalek b/t kfarim and krachim. isnt it also a kasha according to the first 2 terutzim (machlokes tannaim or rabanim is modeh with beis dira)?
I do not see that the Gemara is asking a stira in R' Yehuda. The Gemara is asking on the distinction that we just said between synagogues used by anyone who enters a large city, and between the Beis Knesses used only by a few people in the village. According to the first 2 answers on 11b it does not matter how many people use the Beis Knesses.
According to the Beriasa at top 12a it is only Yerushalayim that is not metemei with negaim; or according to R' Yehuda only the place of the Beis Hamikdash; but we can infer from the beraisa that a shul with many users arriving from everywhere would be metamei with negaim, which presents a difficulty for the distinction that the Gemara just made between kfarim and krachim.
Good Shabbos
Dovid Bloom
i was asking based on the way tosfos learned the sugya.
Tosfos writes that Rabanan agree with R' Yehudah and it is only R' Meir who argues with R' Yehudah.
KOL TUV
Dovid Bloom