I saw a ticket in JIRA for an inheritPLUS binding. I think it would be great especially for javascript/meta keywords. Tags for child documents
from Ryan
This would inherit the parent values plus append whatever is included. For example, use it to include basic Javascript in a header section but change a specific page to include an extra bit of CSS as well.
http://svn.modxcms.com/jira/browse/MODX-16 <-- go here and vote for it
