Tables Don't Respect Reference Orientation--why?

I notice that the spec says that only writing mode determines the cell 
and row progression order. I'm wondering why this is--I can't 
immediately think of any reason that tables shouldn't be rotatable just 
as any other reference area is--that is, the interaction of writing-mode 
with reference-orientation seems no more complex in a table context than 
in a multi-column page context, for example.

Have I missed some hidden complexity?

Thanks,

Eliot
-- 
W. Eliot Kimber, [email protected]
Consultant, ISOGEN International

1016 La Posada Dr., Suite 240
Austin, TX  78752 Phone: 512.656.4139