Even though many people would take issue with using 10% (a lot of practitioners like 5%) and Dr. Awesome has some serious issues with data retention policies, if you always follow Dr. Awesome's advice, you'll win 9 times for every time you lose. I'll take those odds.
Say Dr. Awesome also has one additional problem: one time of twenty, regardless of the results of the A/B test, he just can't help himself and says "It was Awesome!" anyhow. If you follow his advice, you'll now win approximately 5 times for every time you lose. I'll take those odds, too.