UPDATE: It looks like Microsoft Dynamics GP Support Services Blog had posted this article before Collins Dynamics GP blog. You can read both anyways.
May 31, 2012: Nicole Albertson from Microsoft Dynamics GP Support Blog explains Table Links in Extender – Nicole, which can be used to remove an Extender record when the master record is deleted.
The concept of removing Extender records when master record is deleted is very very crucial. This post, hence, is important.