A little paraffin wax goes a long way preventing rods breaking at the ferrule. Still, I've had several clients break rods because they didn't pay attention to the signs that a ferrule was lose. When your cast isn't going as far or is dumping on you,,, check your ferrules. If you hook a hard fighting fish like a 20 pound Striper and you have a loose ferrule it's going to be a sad day for you.
Ferrules working lose is much more of an issue with the heavier sinking lines. Some go as far as to black tape the ferrules together to prevent them from working lose.