My husband went to the range with his friend last week and noticed him using a rather odd grip on his pistol. My husband asked him “What’s with the weird grip and why don’t you hold your firearm properly?”
To which he responded that “So and so says it’s the right way and blah, blah, blah….”

I should add at this time that the friend is a novice with firearms, my husband having just gotten him interested in them in the last couple of years; but he is merely adequate. This fact I attribute to his utter refusal to listen to advice from someone with 37 years of experience in handling weapons. After several failures to feed, and failures to eject caused by his protruding thumb impeding the slide, he went back to the way he was shown, which is a proper two-handed grip (pictured below). 

Turns out he saw the "odd" grip on the TV show “Top shot” and figured that since those guys were on TV they knew more than my husband did about shooting. That didn’t seem to work out too well for him. I saw this grip on the show myself afterwards and, for the life of me; I fail to see a benefit to this grip style. As a matter of fact, if you become accustomed to this grip style and then get your hands on a big bore revolver like a .500 magnum, you could very well lose a thumb. I’m not a competition shooter so maybe I fail to grasp the concept, but that’s doubtful

At my gun club, my husband consistently out shoots guys that are competition shooters (with multi-thousand dollar custom rigs and custom hand loads) with his $500 off-the-shelf PT92 AFS and off-the-shelf ammo, on occasions when they happen to bump into each other. They always try to get him try shooting competitively, but he’s just not the competitive type. But I do know that by holding the weapon in that odd manner you do not have a firm hold of the weapon, and your thumb could impede the slide. If shooting self defensively, the last thing you want to do is cause a weapon malfunction. That could cost you your life.

My husband’s grip preference is the one in the middle photo above, and it works very well for me. This is how he teaches people to hold their weapons when he is instructing, but I suppose you should go for whatever works well for you. It’s not like I’m on TV or anything…..

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"The world is filled with violence. Because criminals carry guns, we decent law-abiding citizens should also have guns. Otherwise they will win and the decent people will lose."
- James Earl Jones