The internet is flooded with gun training. Some stupid, but some very high quality training. Instructors are more so at the finger tips of people looking for good content to learn the basics than ever before. A very large part of that is YouTube. Whether people do or do not like their policies they provide so much content it is mind blowing. That is a good thing and a bad thing. A good rule of thumb I have used is to try something once. Try and be like a porn-star and say "I've never done that before". Go ahead, say it with me!
While we all get to times when we feel we are very good at manipulating our guns, there is always more to learn. In my opinion as long as an instructor is teaching something that does not go against the gun safety rules it is worth trying it. Even if you try it dry fire at first to see how it feels. I was once an asshole, I know shocking. I made a video saying that power stroking the slide was the right way to manipulate the slide on a reload of a pistol. I believed at the time gross skills were better than fine motor skills like using the slide stop/release. Funny thing is now, years later, I hate that way! I believe now if you can manipulate the trigger and magazine release, why the hell can you hit the slide stop/release? I shoot and reload faster now and it works better for me. But at the time I saw a video by a prominent instructor and ran with it. I took it as gospel. It worked for me at the time, but now I wish I would have had an open mind to other ways.
Honestly the person in my life that really has helped me to be more humble just in general is Nate Murr, inventor of the Gripstop. He is like a gun zen master. His philosophy, one I agree with, is who cares how you do something as long as you are getting your hits. If you go look at my video I did with him called "Exaggerated C-Clamp Rifle Grip: Hype or Not?", the comments in their show a ton of non-humble people. But there are also people who just say hey I tried it and it did or did not work for me. But those people who like adult conversations sometimes get drowned out by the morons who "know everything". Just remember, until you try something you don't know how it works or if it works. It might look dumb, but try it. Then formulate an opinion based on fact not idiocy.