Don't think this has been stated before. Basically some of the siege options are ridiculous.
1. Bribing the commander to open the gate: Firstly, after the initial group, enemies spawn OUTSIDE the walls. My men tried to run through the walls, which was my only hint as to where the enemies were. Even dragging my men outside by getting them to follow me didn't work, as telling them to charge resulted in them charging back through the gate! My second problem with this is that the follow up fight in the street is exactly where we spawned in the first round, this time with just about 3 on each side, which is pretty bizarre. Don't have a problem with the 3rd round inside.
2. Trying to open to gate: Basically results in my army charging through the open gate into the enemy army. It's kinda weird that the gate is already open for me to charge in. The first time I tried this I expected to be fighting my way back out with a group of men, not charging in
Also, bizarre incident involving Tver. I already own it, and it was besieged by some Swedish guy. I walked in to talk to the Mayor (and as you cant talk to him from the menu during a siege I went to walk around the town), just checked buildings and things, then left. Immediately got a message telling me how awesome I was for capturing Tver, and whether I think I should it recieve it or not. Got out of that screen, and the town then had no garrison and wasn't besieged any more (the Swede was still outside but I guess the game told him where to go...)