I didn't do Jamils particular recipe, but I brewed a hazelnut brown ale several months ago and I didn't like it much at first either. It was wayyyy too much hazelnut flavor, masked everything else. And I only used half the amount they recommended. However, after 3-4 months, it did mellow out and is now much more of a background flavor. Still don't know if I'll do it again though. i'll probably just stick to normal brown ales from now on.