Lines before mishnah. Before Abayes answer there can be no other way to understand the 2nd braisah. The set of 4 (rishonim) counting serves no purpose. He needs to redo them after the set of 3 and they don't help to prevent needing to redo the 3 set. The braisa itself doesn't make sense at its literal meaning. Indeed TOS Rosh incorporates this into the gmaras question. But Rashi goes out of his way to assert that the gmaras question is only one of contradictory braisos. How does Rashi learn the first braisa before Abaya and with 1st and 2nd literal and making any sense!?
Daniel Gray, Toronto
1) It all makes perfect sense but you just have to know that the terms rishonim and sheni'im switch around in the middle of the Tanu Rabanan. Also, there is something slightly surprising in Rashi, in that he explains the beginning of the sugya according to Abaye's pshat, which is only mentioned later in the Gemara.
2) Yes I agree that before Abaye's answer there is no way to understand the 2nd braisa. However this is not a question on the Gemara. It happens many many times in the Gemara, that without the explanation of the Amoraim there is no way to understand the braisos.
3) Daniel, you write "the set of 4 (rishonim)". You are not using the language of the Tanu Rabanan, because in the Tanu Rabanan the set of 4 are called sheniim, since the 2nd group in the Mishnah are a group of 4.
4) However it is true that the set of 4 in the Tanu Rabanan serve no purpose. This is because they were used first, which means they were used out of order and therefore achieve nothing, as the end of the Mishnah 62a states "Lo Assah veLo Klum".
5) Now, the language of the "Tani Chada" switches from what we have been accustomed to up to now. "Sheniim" now means the ones used second, not the ones mentioned second in the Mishnah, as we had been calling them up to now. So sheniim now means the set of 3, not the set of 4 as we had been calling them up to now.
6) I do not see that Tosfos Rosh is different to Rashi. He also writes that the braisos are contradictory, and that we do not know what the second braisa means. We can agree with that!
Wishing you a very Happy Chanukah