> it kept you from doing something that seemed safe, but
> then you realized that it was actually telling you
> something important.
One of the reasons that I know Rust is on to something is how often I've seen this scenario occur on IRC. It's great to watch someone come in with a complaint about appeasing the borrow checker, only to later realize that what they were attempting to do was actually subtly unsafe.
It's also really a pain now to get the borrow checker to be happy with boxed structures now that box isn't implemented in the compiler. You need to first borrow the whole structure, and then things within it.
For the former point about things that the borrow checker doesn't have enough information to allow, see http://www.reddit.com/r/rust/comments/279yw3/borrowing_from_... for an example.