This is the way IE have implement RTE features in their browser, don't ask me why.
If you want it to move only one line at a time then the Mozilla browser
has implemented RTE features in their browser in this way and it's also
a better browser.
http://www.mozilla.org/products/firebird/
I use it as my default browser now, and can't see why people still use
IE which is becoming outdated now and from I have read MS have stopped
producing stanalone versions of IE so I'm not sure how much longer
poeple will keep using it.
Edited by -boRg-