Last modified date with label expressions

A nice additional feature for the already great function Label Expression would be to display the date of the last modification of a view or concept like `$view{modifieddate}`.
 
I have basic knowledge of how parts of Archi and coArchi works so i figure this would not be a straight forward implementation.
 
Is there a way to get Archi to hook up with events from a plugin? I guess this will require a more extensive implementation with at hook-editor and a set of pre-defined actions within Archi.
 
If a hook "Saved Object" are registered from coArchi and connected to a "Set Propery" action the existing label expressions will already cover the actual feature request.
 
Just a thought I’d like to share. The actual feature request would give me some great benefit. The thougths about a more generic solution just popped out of my head and could be totally ignored.

Start by tracing the existing Label Expression feature in Archi and coArchi, then review the proposed plugin event hooks, including “Saved Object” and “Set Property.” Determine whether the requested modified date can be exposed through the existing expressions; done means a view or concept can display its last modification date reliably.

Written by the indexing model from the issue text.