From Lisa Dusseault:

Over the course of reading up to section 4.3, I discovered:
- There is such a thing as a flow (mentioned in the abstract, defined in section 2)
- There is such a thing as a session (mentioned in the introduction, defined in
section 2)
- There is such a thing as a Messaging Association or MA (defined in section 2)
- Flow != Session (may be one-one, one-many or many-one, according to 3.5)
- MA != Flow (section 4.2.2)
At this point I'm still confused.  Isn't at least one of these totally 
up to the NSLP? That one should be nearly removed from mention in the 
document, and the relationship of all three discussed all together up 
front.