It's an '06 Elantra which was the last one before the model update

Ah, ok. We're driving a '10 and a '11.

I was surprised to see that the California driving manual has been updated to support what I say here: http://dmv.ca.gov/pubs/hdbk/signaling.htm Sounds like lowered hand position while driving is now actually consensus and the meme just hasn't quite penetrated.

Great! That's the sort of thing you should be linking to in your post. (No need to have a list of references; direct links are better.)