>However, in my testing, ? tag() (NO number included) returns the name of the currently selected tag in the currently selected table (just what I want) and ? descending() returns the descending state of the currently selected tag in the currently selected table (again, just what I want).
>
>Because this activity is undocumented, my question is - Can I trust the behavior that I have seen to be consistant.

They've worked fine for me for quite some time. As long as table is selected for TAG or ORDER, and as long as order is set for DESCENDING...