I heard this the following one today, and I agree with it completely. If you are taking your bike to an LBS for service there is a very good chance that the wrench knows a lot more than you.
"Half the people who come in here listen to me. The other half look at the internet and think they know everything." -- Alberts, professional bike mechanic since 1949.
What's your favorite LBS quote? BTW, if you'd like to bash the LBS please start another thread. Thanks.