There is nothing wrong with experimenting different cross class skills. However the role of a tank is to build enmity and using mitigation skills to take as little damage as possible so using blood for blood when you are tanking is an awful decision to make. Don't get me wrong there might be some situations as off tank where an increase in dps is welcomed but when your actually tanking is not one of them.

When your main tanking your dps is the last priority and even then its not important in the slightest.