Another reason understanding how autism is diagnosed is necessary before pursuing an evaluation

My first ever conversation with a practitioner about an autism evaluation (for myself) went like this...

Him: I have some questions before we move forward. First, did you have a speech delay?

Me: No... 

Him: Well, that's a requirement for an autism diagnosis.

Me: Really? Because my son was diagnosed and didn't have a speech delay.

Him: Well, there are other factors, but that's a really important one.

Ok, next question. Do you have any repetitive movements... like flapping your arms?

Me: I bite my cheeks and lips constantly...

Him: Well... biting lips isn't really what I was going for. Have you ever flapped your arms?

Me: No... but my diagnosed son hasn't either.

Him: Well... flapping arms is something we consider extremely important, and I'm pretty conservative when I diagnose autism.

(End scene)

I knew within 5 minutes that pursuing an evaluation with this practitioner would have been a very frustrating (and costly) waste of my time. 

Which is why I posted earlier how important it is to understand how autism is diagnosed before pursuing an evaluation...

But more than that, how important it is to prepare an exhaustive list of examples from your life before engaging with anyone about an evaluation.