Another chlorine question

[waterbear]

CarlD just pretends he doesn't understand the chemisty but he does that to eveyone that doesn't have the password or knows the secret handshake! (He's NOT kidding about it either! The initiation ritual is just unspeakable and horrifying, and involves learing about working with huge quantities (ususally 10000 gallons and up) of dihydrogen monoxide, which can kill you if it gets in your lungs! See the posts in the China Shop section for more info)

Seriously,
Like he said, if there is enough of a reserve of FC in the water to handle the organic load there will be no CC formed. This can happen in a perfect world. In the real world if there is over .5 ppm CC then you need to shock to get rid of it becase in the real world things like rainstorms happen , the dog jumps in the pool, the 3 year old decides she doesn't want to leave the water to tinkle, the teenages invite 30 friends over for a pool party, and so on!