I would have to disagree with your point about there not being MG years ago and kids only read adult. Children's books have been around for as long as there have been books. It's YA that is relatively new, where teens suddenly now have their own market as opposed to just simply reading adult books. That being said, I think it behooves writers of MG to read the old stories, yes times were different and it's important to keep that all in mind, but I think they would notice a lack of condescension in many of the classic MG books. Re-read PETER PAN for example and I think folks would be quite surprised how grown up it is. I definitely agree that one oughtn't write down to kids. There are things to keep in mind, they aren't adult books after all, but kids like can handle a lot more than some people think.