No, I'm not saying that you should usually only fire once. In the hands you posted, sure, there was only one case where I advocated firing the second bullet. That doesn't mean that there aren't many more cases where firing the second bullet is appropriate.
JSampras1, you should read the following post on firing the second barrel; it's one of the best I've ever read on the subject and I guarantee that it will illuminate the concept for you:
http://forumserver.twoplustwo.com/sh...Number=8710077