Here's the problem with being bullyproof, you can get in trouble for properly taking care of a bully.
Well, that is a conversation parents need to have with their kids. Yes, the child may get in trouble, but the long term results of getting in trouble vs the long term results of being a victim of bullying and not standing up for themselves has to be weighed. In some cases getting in trouble, hopefully with support of the parents is the favourable option when other options have proven ineffective.