If an approach has a hold in lieu of a PT, but the chart says
"No PT", is the hold optional, or is it only available with ATC
authorization the way a PT would be in this situation?

I was looking at the ILS 2 approach into EEN, and there is a
segment at 4000' from an IAF at the GDM VOR marked No PT.
The intercept altitude for the ILS is 2600', which is a fairly
quick descent along the localizer (though certainly doable).
If you wanted to take a turn around the hold to descend, do
you need ATC authorization the way you would for a PT? I can't
tell from the wording in the AIM though perhaps I'm missing the
place where it is spelled out.

--
David Rind