פירוש על ברכות 29:22

No contradiction in R. Judah agreeing with R. Judah the son of R. Simeon b. Pazzi, although in the matter of the inaudible Grace after meals it was concluded that he allows it only post factum.

That even ab initio it is permissible for a deaf man to separate Terumah.

That only post factum is the inaudible Grace after meals valid.

So M.; not "there is a Mishnaic teaching" as in edd.

Not on their audibility.

As to introduce R. Meir's teaching into the discussion.