What is realism on left for dead 2

Realism in Left 4 Dead 2 is a game play mode, sort of like campaign but :
1. Outlines around the Players, Weapons, Items, Pinned Survivors, Ect are REMOVED.
2. Common Infected can take more body shots than normal, Head shots are 1 hit kills.
3. Dead players will stay dead unless revived with a defibrillator or if you reach the safe room.
4. Witches Instant Kill on any difficulty except Easy.
5. Witches are harder to "Cr0wn".
6. There is a significantly increase in witch appearances.