[Avodah] The Concept of Authority

[rabbirichwolpoe at gmail.com]

Mareh m'qomos
Hullin 100A
Avodah Zara 74a
Rif
Tur YD 101
BY  YD 101 D"H Haticha hor'uyah l'hiskabeid

My translation:
"...Even though the Rif appears to not "have" this Mishnah, nevertheless
all the posqim "nimnu v'gamru"
To decide the Halachah that a piece of "n'veilah shehee r"uyah
l'hiskabeid" is not nullified

Questions:
1 What is the Talmudic authority of "Nimnu v'gamru?"
2 What is the POST- Talmudic authority of nimnu v'gamru?
3 Was the BY using this term correctly?
OR
4 Was BY C"V conflating Talmudic nomenclature in a non-talmudic Halachic
  discourse - thereby confusing us as to the proper valence of the term?
5 May WE use this term now - since the BY used it?
6 Is the BY merely reporting a p'saq of a virtual BD with nationa
  authority?
OR
7 Is it just the BY's opinion and we can follow the Rif despite this
  statement?

KT
RRW
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