Originally Posted by TVthePunisher
According to Fat Man Ross, he was able to save and reload to re-enable achievements. When I get close to earning an achievement, I will try the same to verify.
I think he means, you can use the cheats until you reload or quit the game. If you save the game after a cheat has been activated you can't unlock achievements because the game has a 'cheats activated' stat.
I havent got the shark achievement so I can doulble check to confirm.