When your senior says he may as well stops working as I'm always refactoring his code...

Same sentence says I copy what you've done in other places so I don't see why it isn't good enough. By copy he leaves redundant code in there too.

Am I a being a douche is he just being over the top?

- He writes code and expects it to live for a long time.
- I write code and will go home and refactor my own code.