A more flexible rule that also might help a little would be to require a separate justification for the use of time to be filed for every single invitee.
It's just like of the signup process on your landing page. Make things you want to happen as effortless as possible -> make things you want to happen less more effortful.
In an evil afterthought: If people still keep inviting to many others to meetings, make the filing of the justifications only possible using a special intranet page, and make your least capable intern code that page. That should sort it out. }:->
It's just like of the signup process on your landing page. Make things you want to happen as effortless as possible -> make things you want to happen less more effortful.