[jandrese]

I'm pretty sure the mechanics of the anti-cheat are kept obscure to prevent cheat makers from adding anti-anti-cheat tech to their product.

[saagarjha]

They are but get promptly reverse engineered by modders and hack developers. Many of the core techniques remain the same.

[swarnie_]

Pretty much this, its intentionally kept as a blackbox.

[midnightclubbed]

Some solution are a blackbox to the game development team (and run as a post process during the game link or as a separate executable monitoring the game and system).

There is a huge and lucrative economy around cheat development that encourages a fair amount of paranoia from game developers.