I really don't understand how anyone could defend Rahul "thinking" of using knife in buzzer task.
It wasn't just a thought. If it was just a thought, we or the housemates would've never known about it. Because Rahul himself won't have told anyone. He would've realized that it's a completely stupid thought in less than a minute. Gauhar need not have to tell him that it's stupid to use knives.
The fact that he started preparing for the task, discussing with other housemates and Gauhar, and they had to tell him to not use it, makes it NOT JUST A THOUGHT.
You can't compare it with people having random thoughts of doing crazy stuff like killing someone. Because we just think it as a fantasy. We never think of doing it practically. Rahul was practical about using knives.