That is also a good way of fortifying your gate more.
To me, just about anything that will help you attack the backs of your enemy
Is a valuable addition.
Not only will the indented gate help you attack your enemy while they batter at your gate,
But the enemy will have a much harder time getting any siege engines to it.
There is one problem... The indented gate,
In addition to a corridor with a second gate will stick very far out into your city.
From the looks of it it will reach about 4 or 5 steck lengths in.
Though it will make it hard to attack,
If they ever did break through they would already be far into your city,
Which is VERY bad.
The thing you most want in a siege
Is the enemy to be as far away from the center of your town
(Or the next wall) as possible.
This gives you more room to fight in,
And more room for them to have to go through to get to this key point.
If it is 4 or 5 lengths in already they can attack your armies flanks,
And get to the center of the city faster, and gain control.
You may want to choose one or the other,
Or curve your corridor so it loops to another part of your city.
Curving the corridor has certain advantages to it that may well hinder the enemy.
If you have two gates that are quite close together
Then you can curve the corridors so they open up on to the same space,
Maybe 3 or 4 lengths apart from the other gate.
That way the enemy walks into a choke space.
