The situation is as follows:
1. The original nc-dap code makes invisible any
coordinate variables that are mapped to
OPeNDAP map variables inside Grids.
The netcdf code mimics that behavior.
2. Different OPeNDAP servers translate netcdf files to
the DAP format in different ways ( I just did the test
to verify this).
a. Hyrax servers place coordinate variables inside Grids
as map variables. This means (per #1) that they
are invisible to clients.
b. Thredds servers duplicate the coordinate variables
so that they are outside of the Grids and hence those
coordinate variables are visible.
3. When serving up non-netcdf files, the translations
may or may not place the equivalent of coordinate variables
either inside Grids or outside. See for example:
http://tds.hycom.org/thredds/dodsC/glb_current_analysis
Personally, I think that the Thredds translation is preferable
to the Hyrax translation, but that is just me :-)
In any case, the problem is not with the clients, but rather with
the servers. Perhaps the community can come to some resolution on this.
Also, as I mentioned in another message, there is an alternative:
If you have compiled netcdf using --enable-netcdf4, then you can
do an ncdump -k3 and it will present the DAP data in netcdf-4 format,
and in that format, everything is visible.
=Dennis Heimbigner