Yeah I agree with this. Although legally permitted, I generally avoid roads that are 35mph+ with high traffic and no bike lane. It's just unpleasant to constantly have cars come up quickly behind you and narrowly change lanes. And many of them have no idea what the law is so they honk and get all agitated by it. Sure, it's their problem and not yours but it still makes it more hectic and less fun.

Sometimes you can't avoid these roads on a particular route but I try to minimize them. If you find yourself on a busy road though, take the lane or you will find that cars will nearly (or actually) clip you.