The "FIE" is a legitimate practice, that can be a help in certain situations. While primarily useful as a "training tool," to help in learning a desired projection of the voice, there are circumstances where its use in performance may help the performer to do a better job.

Anyone who does it in performance just "because it makes me look like a folk singer" is certainly to be pitied.

If a performer uses the technique because it helps the quality of their performance, then it would seem appropriate to applaud their knowledge of what makes their own performance the best they can do.

To a certain extent, it is the mark of an inexperienced perfromer, but folk is where we accept and applaud the tradition that is presented/preserved first, and the performance as a secondary element.

Judging too harshly may mark the "judge" as "not quite into" the folk element.

I guess it would depend a lot on whether we are expecting a professional PERFORMANCE or whether were sharing someones appreciation of a song.

Try it sometime, and see if it helps (in a private practice session - of course).

John