embedding marcxml question

Re: Patrick's question the other day on what I mean by extension, and 
whether one could embed, say, MARCXML *within* the bibliographic file 
...

A developer would have two options:

1)  convert the specific chunks of extension data into this metadata 
format (the RDF) and embed it inline in the file. This would be the 
normal case for extension, and would probably typically be simple 
properties.

2)  just include it as is as another file. So say the LoC wanted to 
archive ODF documents; they can easily also include a separate MARCXML 
file if they want (though there's not much reason to do this 
practically).

Bruce