I haven't read all of this thread, and maybe someone's already suggested this, but if you're looking for people with actual experience, ask them to bring in some work they've already done and have them explain it to you. They can show you the code, discuss the techniques they used, etc. Making such a requirement known in advance would probably scare away most of the inexperienced and the B.S. artists.
"Ignorance more frequently begets confidence than does knowledge."
-- Charles Darwin
"I am invincible! Invincible...OWWWWWWWW!"
-- Homer Simpson