What is meant by 'Ownership role' option in the Add/Edit role page?

Checking the 'Ownership role' option just displays the user as an owner on the project home page. He is not the Project Owner and has none of the Project Owner permissions. The user who has this option enabled on a project gets all the email notifications that an owner is supposed to get.

For example:

1. When an Announcement is suggested
2. When a role request is made
3. When posts are made to Forum/Mailing Lists etc. In such cases, the user receives the email notification but cannot approve or disapprove the requests that have been made.