I think you've pretty much explained your objections well. I will take exception to one thing;
"If you are saying that there is any way to change or "intensify" certain genetic instincts, I will tell you you are wrong"
Actually he's right. Intensifying certains traits is pretty much the whole ball game in breeding and it's what facilitates the development of new breeds. [Ex: intensifying the use of eyesight or scent in hunting (sighthounds & scenthounds) ]
Second his arguement (that PB have a "killer instinct") is entirely illogical. If they were selecting for an unusual instinct of this kind the breed in general would have this trait. This would mean that owners of PB could never own more than one dog at a time because they couldn't safely put them with another dog. (previous example: put a predatory dog with livestock simply gives him targets for his instinct)
Now I know a thing or two about dog breeding and believe me you have to have more than one dog.
Thanks very much, Varda.
If they were selecting for unusual instinct of this kind the breed in general would have this trait.
That is why I asked the question I asked about the "killer" instinct. I define instinct a bit narrower than most folks, and don't use the term synonomously with trait. (wrong as it might be) Although traits and instinctive behavior are both genetic, I think of instinct as specie behavior on the whole. Bees dance and bats echo-locate; something they cannot avoid. At any rate, I believe I understand what Jeff is saying now about killer instinct.
This would mean that owners of PB could never own more than one dog at a time because they couldn't safely put them with another dog.
Exactly. I shouldn't be, but am always surprised by the number of people who believe pitbulls come into the world as "natural born killers." The truly sad part is the ignorance on both sides. A lot of good hearted souls as well as the scum that dogfight really believe this.