I'm not suggesting that I agree with the logic, I'm just stating I can see some logic behind the statement. However, to answer your question, it is much harder to conceal any of those items. If you carry a chefs knife and intend to use it as a weapon, you would have to be careful in how you carried the knife to and from the location of the crime so that you don't cut yourself. On top of that, a chef's knife is quite large. A switchblade can be easily concealed in ones pocket and hidden in a sleeve then used and concealed again with virtually no risk of cutting the assailant.
" Baseball bats, tire irons, icicles: almost anything can become an untraceable weapon."
Perhaps I didn't pick my words correctly. What I mean is that I could stab somebody with a switchblade without drawing any attention to themselves after the fact. Not the same can be said about bulky items such as baseball bats, tire irons or even a chef's knife.
Fair enough ... However, there are several things I could use to commit a crime and easily conceal afterwards. A paring knife in a sheath or even a USB cable could be used as a weapon and easily concealed. These two objects have very deadly potential but their primary purpose isn't to cause harm. For something that is created to cause harm, that is a different discussion. Otherwise, we would need to talk about registering your Cat 6 cables with the government and the box of cable sitting in your garage would be considered an assault weapon.
I don't buy the argument that assisted-opening knives should be more controlled because people think they were invented to hurt others. It's technology that many people have found utility in for meaningful purposes: construction workers, sailors and ships' crew, hunters and fishermen, and emergency response personnel. I think many of them would tell you it's incredibly helpful to be able to quickly open a knife with one-hand when you need it. Unfortunately, we live in a world where everyday things have inherent risks if used improperly. Sometimes they are used the wrong way with malicious intentions and the easiest way we can think to prevent trouble in the future is by regulating the objects, not the behavior.
I think switchblades fall prey to a particular stereotype, hence their "bad" nature. But, ask any diver/hunter/tactical knife wearer - they are strapped to the lower leg/calf in a holster, easily concealed under a pant leg.
" Baseball bats, tire irons, icicles: almost anything can become an untraceable weapon."
Perhaps I didn't pick my words correctly. What I mean is that I could stab somebody with a switchblade without drawing any attention to themselves after the fact. Not the same can be said about bulky items such as baseball bats, tire irons or even a chef's knife.