Mark, (well, we're hijacking this guy's post all to he**) I used to be a homebrewer. Even worked in the Tempe homebrewing store for a couple years. (The owner is a world-class @$$hat!!)
Smoking barley should be done VERY MILDLY!! Alder would be a good choice, bit done very lightly. You should just BARELY perceive the smoke in the beer, and just a hint in the barley, after smoking. Also, the grain bill should only call for 10% at the most, of smoked barley.
Rauchbier done RIGHT is a decent brew to drink. Done with a heavy hand, it tastes like licking out an ashtray!
Funny, smoking meat is the same way.
As my brother Sterling (Skouson, here) says, the smoke should whisper, not yell!
steve