I'm not sure if this has been mentioned previously here, but I thought I'd post a strategy I've stumbled across for when I'm defending in a siege in the early game.

Basically, when you are sieged, check the attacking army before you go to battle. If they look like they are going to rely on the RAM, set up 2 or three archer stacks just inside your gate, and set them to use Stakes. Try and get them as close to the gate as possible. Line up a couple of melee units behind them.

Then when you start the battle, run your archers back up on to the wall to begin peppering the attackers as normal. Move your melees up just behind the Stakes and set them to guard.

When your flame arrows fail to ignite on the Ram and it breaks down your gate, watch as the attackers start to stream in through the gate, with the ones at the front being impaled as the guys behind push in. This works particularly nicely when the attackers have a large Cav presence as they are really skewered nicely.

I've tried this a lot on my VH/VH England game, and it has gotten to the stage where I've managed to win battles I'd no right to.

Best example is in Dublin, where the Portuguese landed an attack force. I was caught unawares as they had been my allies, and I only had a force of Hobilars, two peasant archers and two town militia in the barracks. I was up against about three units of heavy melee, about 4 or 5 units of cav and some regular melees too. I set up the Stakes in a V just inside the gate, with the archers back a bit on either side so they could shoot over at the backs of teh attackers on the other stakes, and the melee's just behind the stakes.

It looked at first that I was going to just get overrun as their whole army flooded through my measly wooden walls, but as the guys at the back pushed through there was nowhere but onto the stakes for the ones at the front to go.

One word of warning, is that when the attackers turned to rout, I tried to chase them with my hobilars to gain some exp, but realised too late that even when you are running through stakes from behind, the horsey's die! I don't quite understand that and maybe its a minor, but either way, I killed nearly half my horse before I set them to walk through the stakes!

Anyway, thats the first thread I've started offering a tip of sorts, so I hope its helpful, and that it hasn't been discussed to death elsewhere.