What is the scope of the default data session among objects instantiated within the same MTDLL? Do the same rules apply as with public memory variables?

For example, Assume the init() of a MTDLL does:
USE MyTable
...within the default data session (and does not explicitly close the table when object is destroyed).
What is the status of the default data session for the _next_ object instantiated from within the same MTDLL? Is MyTable already open? Does it depend on which thread is actually associated with the new object (i.e., table will only be open if new object is on same thread that was associated with the object that opened the table)?

I need to ask the same question regarding private data sessions too, just to be sure that I'm not making wrong assumptions.

Thanks very much.