Thank you Phil, but I don't think it will change much.
You need 3 breach to assault Carthage. At best, when lucky, you will have 1 breach from the siege, rarely holding the following turn. With SiegeWork, you ll get another... That's one breach lacking, all the more since you would have to play the "siege work" when the city has already 2 holes, and pray for the breach not to be closed.
That's why I proposed instead destroying the wall little by little. As I see it, Carthage had several layers of walls, so this would represents the layers being "occupied" one after the other