Now I am a believer. Actually, I have never disbelieved, but have had no concrete proof until today.
I bought a breakaway collar for my adolescent cat the other day as he has outgrown his kitten collar.
It is sized correctly, not too loose, not too tight. It will adjust as he grows.
He came in today without it. I thought at first I may have not had it adjusted incorrectly and he pulled it off.
I went outside to do some work and found this.
There are claw marks on the wood around it, so he did struggle a bit, but the thing did it's job.
Was worth the extra buck over the plain one, I'd say.