Questions on <datatemplate> (ref. call for exclusions)

Hola,

Recently, I became HP's representative to the HTMLWG, and
so I am working hard to review the WD before the Call for
Exclusions deadline of 6/20. There are a few sections that, 
being incomplete, are difficult to assess.  Unless I receive 
counsel otherwise, I'll be sending several requests for
clarification, one topic per email.

First topic is <datatemplate>. I see that this is marked
as "Being considered for removal" in the WHATWG draft, so
I welcome any guidance on its likely fate. That said, it's
in the WD, so HP must review it. Questions:

1. Are there publicly available examples or explanatory 
   text for this feature? Also of interest would be any 
   discussion of its genesis or motivation from the HTML
   or WHATWG mailing list archives. I couldn't find any.

2. This section cites the "Levenberg data node algorithm"
   and "Levenberg data template algorithm". Could someone
   please point me to a reference outside the WD for these?

3. What are the allowed values for the "mode" attribute?

4. The "condition" attribute definition says: The condition
   attribute, if specified, must contain a valid selector. It
   specifies which nodes in the data tree will have the
   condition's template applied. [SELECTORS]  But the link
   on SELECTORS points to References, which is empty. What
   kind of selectors are these?

   (The link in the WHATWG draft is broken, btw.)

5. The definition of <nest> says "The nest element represents
   a point in a template where the user agent should recurse
   and start inserting the children of the data node that
   matches the rule in which the nest element finds itself."
   Could you please say more precisely what recurses here?

thanks,
Matt
--
Matt Bonner
Hewlett-Packard Company