mvwin, windows and derwins/subwins

[Bryan Christ]

Can subwins be derived from subwins?  I can't seem to find any concrete 
documentation on this other than an unsettling comment in the man pages 
which says "The subwindow functions (subwin, derwin, mvderwin, wsyncup, 
wsyncdown, wcursyncup, syncok) are flaky, incompletely implemented, and 
not well tested."

In other words, is this hiearchy valid:

window->derwin->derwin

If so, what happens to the derwins when the parent window is moved with 
mvwin?  Do the derived/subwins get moved accordingly?

Thanks,
Bryan