I'm playing single player Left 4 Dead on the second to last chapter of the third mission and the AI director is being an absolute ash hole. I can't get more than two minutes into the level before it sends at least 6 swarms at once, plus three smokers, two hunters, two boomers, and a tank, then another three swarms. no weapon upgrades or health items either. It might sound like I'm exaggerating but I'm not.
I'm happy that they developed an intelligent AI to replace traditional enemy spawning, but it would have been nice if they hadn't programed it to be a phucking prick.
Anyone else get an ash hole for a AI director?

Thats Randomness for you.

it states on the back that the "powerful AI director" will give you a different experience each time you play, I have had this problem too just without the tanks.
I suggest you try multiplayer as its much more fun and larger hordes dont tend to be a problem for actual players unlike bots.