Architecture of a Castle.

[Ryan K]

In theory, perhaps. In practice, an approach to any determined defending castle is fraught with danger regardless of whatever side one bears one's shield. Shields aren't very good at protecting someone against projectiles lobbed from the top of high walls. Attackers will not even come within bowshot until defences have been breached, and depending on the aggressor's commander, that may or may not be directed at the gate. Sieges, historically speaking, tend to last only as long as it takes for one side or the other to run out of money, health or time. This can end with the garrison commander surrendering under terms, or the aggressors quitting the field. A formation of troops 'marching onto the castle' is generally a very good way of getting them all killed unless the castle is compromised, or their defenders are broken. So, you tend to keep soldiers out of the way until you know for sure they are going to make a lick of difference.

Siege warfare. Good times.

Edit: As an aside, and depending on the topography of the landscape the castle is perched upon, I'd be investing in breaching the wall on the east-side of the first gate house, but that depends if I have the money to spend on sappers, engineers or a couple of reliable canons. If I just had troops, and the money to keep them happy long enough, I'd just sit on them and wait for them to run themselves out of food, water and hygiene.