DOCBOOK-APPS: TOC and LOT elements in the grove seem to be different...

Hi,

I have noticed that the TOC and LOT sub-trees seem to be different from 
other parts of the grove, in that:

   (select-elements (children (ancestor (normalize "book")))
	           (normalize "bookinfo"))

does not work. This suggests that a LOT or TOC are not properly 
connected in the grove.

One has to do:

   (select-elements (children (sgml-root-element))
		   (normalize "bookinfo"))

Why is there a difference?