I guess smell is reletive to the person. Some people don't have as good a nose as others, but I agree with you and Mobious about the dogs. However, if you get to the point where cops and thier dogs are looking around your home, you probably have no chance of hiding your grow anyways.No and everyone that tells you it does is just fooling themselves. Carbon will only remove so much, even if you slow your cfm's down below half the recommended rate you will still get blow by.
The only for sure 100% removal is through a ozonator.
Mobious is right a cop dog will smell right through a carbon filter in a minute.
Smell is the second biggest reason people get busted so don't take it lightly espesially if your not on the up and up.
Good luck