It also seems that the following it true if use DataSession=2 (Private):

1. The COM object is always created with a fresh, empty, data session. For every instance of the object, you must explicitly USE all tables that you want to have open during the life of the object.

2. When the COM object is destroyed, all open tables in its private data session are automatically closed.

This is what I'm seeing with the tests I'm doing. Behavior here is distinctly different than when you use the default data session, in which case both tables and cursors remain open across instances of the object.