The Hidden Blade Assassin's Creed in Depth

I made this video to show some exploits I found playing the mission "A Narrow Escape" (Sequence 1, Memory 2).
The scripted route in this memory is to follow Altair's ghost on the top of the castle, but as shown in the video there is a way to leave the castle and go back to the village.
1:18: It's not possible to reach the ground into the castle, so you'll instantly desync if you use the stair.
1:55: I killed that guard for fun, it's not needed XD
The city gate is open, so it's also possible to go out of Masyaf. When you reach the end of the map you'll fall in the water that is under every map.
I tried to swim back to the castle's direction to see if there was something interesting, but there are only random stone blocks. At 05:50 I swim exactly under the point where Ezio will break the floor and find a pool underground, but it's not visible.

At 06:52 I found something else interesting: the ledge on the right can't be grasped, but you can reach it by a wall run. From there I tried many things, but unfortunately almost all ledges are not graspable.