SSN 23 stern planes - Why split the stern planes

[feet wet]

In the hi res photos previously posted of SSN 23 the Jimmy Carter, they show split stern planes. What is the purpose of this? I can think of two possible reasons and would like to hear the thoughts of others.
1) reducing the surface area of the plane allows precise control input at high speed similar to an airliner.
2) the ability to counter/control roll at high speed.
Any thoughts?
Jonathan Eno

[thordesign]

Both are correct.

http://www.subcommittee.com/forum/icon_smile.gif

Both are correct.