I can't find the message where you mention HLN, which has a non-radar approach
control. I believe you mention there aren't many of those around these days,
which is correct.

And, at a place that does have a tower and a non-radar approach control it's all
pretty well sorted out with full use of IAPs and DPs except when visuals can be
issued or good weather permits hopefully familiar pilots to request VFR climbs.

Then, there are the cases of VFR towers with no approach control of any kind,
such as Jackson, WY. A bit of grey creeps into that picture since ZLC provides
terminal services and has no radar below the mountain tops. Plus, the tower is
part-time so it goes from one shade of grey to another when the tower closes.

This is grey for pilots, not controllers. The Air Force proved that at Jackson.
After that Jackson got a part-time tower but no remoted ASR (unlike MSO).

What is on the increase are RNAV IAPs at Class G (and, in some cases surface
Class E) airports with no tower and with Center providing terminal services
without radar below the mountain peaks. As a matter of policy, ATC pretty well
walks away from terrain clearance at these airports. It's up to the pilot to
ferret out the Obstacle DP, which in some cases will be in apparent conflict with
the initial ATC clearance.

To make it safe and consistent from JFK Airport to BIH Airport, the aviation
community would be far better served if the initial ATC clearance at the BIH-type
airport included the obstacle DP, then onto routing at the terminus of the ODP,
that would tie to the en route phase of the clearance.

Then, let the burden fall on the pilot to say on a clear day or night, "I don't
want the obstacle DP, I request a VFR climb to XYZ VOR."

The system would be safer as a result. And, with the pending rule change that
may come out mandating obstcle DPs unless ATC assigns a vector or SID, then
perhaps we will get there.

BTW, Billings has an easy vector environment compared to many mountain area
airports. You are basically flat landers to the north and east. MSO should have
it so good.