I agree but if you keep the rivalry even after the task, it makes sense. People do not fight only during tasks, they fight for food preparation, cleaning, etc . So it makes sense to keep away from one you don’t like like to have sweet and sour relations.
Courage is fine, and appreciable, but pettiness isn't. I found Shahzad's refusal to shake Nishant's hand very unsporting. Nishant had as much reason, if not more to, to be pissed at Shahzad, but he at least knew how to keep the task separate from any personal issues.