My little guy (27 months) is going for his speech language assessment tomorrow and I have considered cancelling it a few times for all the reasons you mentioned. I know his receptive language is light years beyond his peers. He says what he wants to say when he wants to say it. He gets his point across in 30-40 words.

I'm sorry to hear about your experience. It is so frustrating when our 'mother knowledge' is dismissed.

Tomorrow is always fresh, with no mistakes in it. — L.M. Montgomery