You're making a huge leap here. I'm raising only had signaling intentionally rather than automatically has made me pay more attention to others on the road. You're claiming that that action which has proven to make me pay closer attention will kill someone.
By not signaling you are robbing others on the road the opportunity to avoid a potential accident should you not have seen them. It's maximum selfish fuck everyone else asshole behavior.
No, I'm not claiming it will kill someone, I'm claiming it may kill someone.
There is this thing called traffic law and according to that law you are required to signal your turns. If you obstinately refuse to do so you are endangering others and I frankly don't care one bit about how you justify this to yourself but you are not playing by the rules and if that's your position then you should simply not participate in traffic. Just like you stop for red lights when you think there is no other traffic. Right?
Again: it costs you nothing. You are not paying more attention to others on the road because you are not signalling your turns, that's just a nonsense story you tell yourself to justify your wilful non-compliance.
There is no such thing as not signaling. By not using the turn signal, you are lying to anyone around that you might not see, signaling that you are going straight forward when you aren't.
Seriously: signal your turns and stop defending the indefensible, this is just silly.