To answer your first question...YES, there has been a time when a REAL water evacuation has taken place.
>For Example: If you go to Airliners.net's home page, in the middle you'll see the title "latest article". Just below that, you should click on "Other Articles" At the bottom of the list, there's an article called "The DC-8 That Was To Young To Die".
This story is about a DC-8 that "ditched" into the waters of the San Francisco Bay area. I believe it occured in 1968. There were no deaths, and the DC-8 was repaired. According to the article, it's still flying today.
You should read this article. I'm sure you'll like it.