Ah yes.
The pincushion units that have changed warfare.
Another thing to consider is the code that has infantry leave the walls if the attackers don't have infantry. I've seen nation attacks with ONLY archers so the infantry charge out into massed archer fire and get slaughtered. Then send in the infantry attackers the following turn to swarm the walls and take the city without any infantry to fight them. That seems to me to be like a similar...taking advantage of fighting code situation.