As a follow up.. I had thought maybe I could force this to work by creating a "mailto" link in the body of the Announcement posting. It won't work. GO keeps re-formatting and eliminating the content.
If I highlight a word, click the Link button, erase the http:// leader in the box that opens for setting the link, type in mailto:email@example.com?subject=set%20vacation&body=[ENABLE]%0Dyes
GO will re-format all of that to eliminate the %20 (spaces), %0D (carriage return) and even buggers up/won't use the ?subject= portion. A basic clickable link is made, but with no subject and no body pre-entered for the user. So that won't work at all. Would be great if it could, because then I just just make this into a Link my users could click on from the Announcement to already put the format in place for them, and they would just need to edit the date.
So.. they cannot select/copy text from the announcement body, and you cannot create mailto links to pre-format messages for people.