Hope_Fowl - 2:48 pm on Jul 12, 2012 (gmt 0)

Webmaster creates a page or pages, or alters a page/pages.."submits" immediately..G's system "time stamps" the submission..original attribution assigned.

No need for a manual submission to Google about changed content. There already is a mechanism which many CMS use: the Google sitemap ping, an HTTP request which invites Google to reexamine your sitemap.