You are forgetting Brian's propensity for cowardice, he would never attack anyone
Also he has a propensity for anxiety and choking as the event approaches. Performance anxiety, which is part of the reason he always turns up shit on stage. With the Cup he did practically nothing and went in on a lark with zero prep, like many here told him to do, and got lucky. Of course he knew he could always fake Cartoon Dogs and drive home.
Practice tests are one thing, scores decades ago are another, but recent history isn't on his side here for doing well on the day of the test (September 8th) and not choking