Thinly veiled cheating, IMO.
Cheating by following the rules? I don't understand your opinion.
I suppose you're fine with so called "castling," too.
Actually, I am. When I play poker, I'm OK with a full house beating a straight. And when I play Monopoly, I collect $200 after passing "Go."
Well why shouldnt a knight gain more favour and become a rook? Seems fair to me.