Questions and comments:
1) Why does atom:tagline go outside of atom:headentry? Why does atom:generator go inside atom:headentry?
2) Does atom:entry get an atom:version? how does it make sense to put atom:introspection into atom:entry vs. atom:headentry? same question for atom:post? does atom:headentry get an atom:edit? if so, can it be used to edit the atom:tagline, even though that's not in atom:headentry? if not, how is atom:tagline going to be edited? ...and so on. There seem to be lots of differences between the contents of atom:head (or atom:headentry) and atom:entry. With only section 4.2.11 being removed, how does this substantially shorten the spec?
3) Could you elaborate on "Allows a straightforward way to implement hierarchy". I think I sort of get it, but this feels like a much bigger shift than the sparse language of the Pace would imply.
4) atom:headentry? he a dentry? what does this have to do with teeth? ;-) Seriously though, why not stick with the name atom:head, even if it is to be some sort of Entry Construct?
