I think the more control you can get yourself under the less severe the symptoms will be, or they will feel less severe. It's trying to stop the thought before it gets to the point of being that irrational, thats the goal I think.

Thoughts grow in power when you worry about them. I agree that if you're hitting a real low or high that this doesn't necessarily work, but for the most part the majority aren't feeling superduperdepressed 99% of the time or really manic all the time, and lets face it, medicine only does so much. I may not feel depressed or manic but my mood still fluctuates frequently throughout the day, and isn't always appropriate.

But that doesn't mean I don't accept it and move on. No use worrying about something that is a part of who I am. x)