Everyone is going to have their own opinion and everyone on the Internet is a firearms expert so arguing over this is going to be pointless, but I will say that you're going to find a hard time locating actual experts that think it's a good idea to pocket carry without a holster, no matter how careful the person is. The holster covers the trigger, keeps the gun perfectly stationary and at the exact same angle for a smooth draw every time (even if you end up having to run or wrestle with an attacker it won't get slanted or canted funny). But again, this is one of those things that you won't convince some people of until they learn the hard way.