yes it does, it all relates to any criticism being made in private, whether it is criticism of choice of material, criticism of diction, or any other criticism.
the op said a matter of protocol or politeness,
something that 3 posters here have ignored, one of them being jim carroll, with his remark about the merits of me helping someone with their singing being enough to make someone go away and take up macrame.
jim, you as usual have failed to adress the point made about teaching or correcting diction, you have as is your want, then taken it upon yourself[presumably as a smokescreen] to denigrate my abilities.
when will you provide any evidence that correcting a persons diction often interferes with accent and dialect.