Exactly the same I have the understanding but it's writing it in the way WJEC wants it. I am just going through Ronan Walters notes and memorising mark scheme answers. The problem is the definitions change, so I tend to focus on the newer papers. I have also got the revision guide to go over things on the spec WJEC haven't asked before, but not sure if there's any point because they want it a specific way and if it's not that it's wrong.