This fails on machines running on a managed network:
path to application support from user domain as text
When the user is logged on as a local admin the returned path is: “Macintosh HD:Users:ladmin:Library:Application Support:”
but when logged on as a network non-admin user gerry the result is: “Users:gerry:Library:Application Support:”
No volume name. How can I get the full path on a managed machine?
Strange.
Does it make any difference if instead of having ‘path to’ return the text, you let it return an alias and coerce the result to text?
(path to application support from user domain) as text
You’re overthinking this one.
If you want the volume name included, don’t use “from user domain”. This ending implies that you want the application support folder for the current user, as opposed to the one at “Macintosh HD:Library:Application Support:”.
Hope this helps. 
That doesn’t make sense. It doesn’t matter where the folder is it should always start with the bootvolume, in this case Macintiosh HD.
I would say it’s a bug