Idle drop by 500 rpm?

I was trying to tell him how to eliminate the timing as a suspect, and I'll be a mutha ****** if somebody doesn't come in and send him off a different direction. It's not about being right. It's about helping the guy out of process of elimination and these guys just jump on and just **** up a good diagnostic flow chart. So I give up.

Yes Process of Elimination, best way to get to the bottom of the problem.