Associations in TM/XML

Hello,

[1] describes the The TM/XML serialization procedure. Point 8 in  
section 3.1 (The Serialization Process) describes the serialization  
of associations. Now following this procedure for an association with  
two roles with distinct players leads to two separate elements, one  
as a child of each element representing a topic that plays a role.  
Most of the TM/XML examples i have seen so far, omit the duplication  
of associations. I am wondering if it is an error to have the  
association only at one of the players. Or is it an error to have it  
at both? Or is both acceptable to allow flexible output depending on  
the requirements of the the TM/XML consuming process.

Lastly, i wonder how should a deserializer recognize that two  
elements correspond to the same association (without item  
identifiers)? The deserialization procedure at [2] seems to create  
two distinct association statements.

Kind regards,

Robert Cerny

[1] http://www.garshol.priv.no/download/text/tmxml.pdf
[2] http://www.garshol.priv.no/blog/62.html