I think he's quite self-aware about the difficulty he has forming statements... I think he's frustrated LONG before anyone has trouble understanding him. I think he's actaully most frustrated when he's alone. I often hear him try and say something over the monitor, and fail a couple of times, and then throw something and call out for me. It's one of the reasons he can't seem to play by himself much...
He alters his speech drastically to suit his audience. I talked to a babysitter about the appt, and she tried using more complex language with him, and she said he really opened up, just over the course of 2 hrs, after having spent a lot of time with her in the past.
On the other hand, I really get what you're saying about adults not having patience for a toddler expecting to be listened to *carefully.* People often stop looking at him, and ask me how he is, because they read his elaborate reply as simple babble --even when it's clearly ennunciated, they just assume he couldn't have meant what he said.
DS gives up completely if you misunderstand him. Even if it's just that there was a car backfiring a block away or something, he won't repeat, just looks dejected and changes the subject.
-Mich.
