Pieter is fast becoming one of Caellach's favourite verbal sparring partners on the IGS, it's a clash of the unstoppable force meeting the immovable object in which two stubborn bastards are firmly sitting in their respectable opinion camp, and come head to head in the belief that they're absolutely right.
He finds him frustrating at times, a zealous nationalist who eats up all the propaganda he was thrown growing up. But he can't fault him for sticking to his convictions and beliefs, and is quietly confident that if they ever were to move off the Gal/Cal topic to something else that they agreed on, it'd be a shit day for anyone who tried to disagree with their stance.
Also he looks like a worthy opponent in a drinking contest, that will result in the suffering of livers.