David just caught me making a stupid mistake, using "external" instead of "native" sorting for KML features. In this case "native" refers to the Postgresql datastore doing the sorting, and "external" means that GeoServer will do the sorting in Java (lots of table scans on backend).
I don't think it's the first time I have made this mistake, I tend to think "external to GeoServer".
I propose we change it before 1.7.0, for example to
external-sorting -> "Sort in GeoServer"
native-sorting -> "Sort on backend (recommended)"
While we are at it, change
geometry -> "Geometry size"
-Arne