Perhaps to a certain extent. But without even understanding their own swing flaws, few would advocate their own compensatory "band-aid" to others who, even if they demonstrate the same symptoms, may not (likely don't) have the very same root swing flaws that result in those symptoms.
It's also worth noting that band-aids are meant to be temporary and shouldn't be considered a permanent fix. They might get you through a bad round on the course, but as soon as possible, you should get to the range to figure out what the root cause was.
I remember from your earlier posts that you've only been playing for a relatively short time now. Have you considered finding a professional to help recognize, and subsequently correct those flaws rather than trying to figure it out yourself?
I agree that many, if not most, high handicappers might not be able to make this swing work for them. I only advocate that golfers who are willing to try something new just give my swing (not just the thumb out, but the entire setup and swing I described earlier) a try. If it doesn't work, it's no great loss. If it works as well for them as it does for me, they will be overjoyed.
I've been playing not quite three years, and am VERY happy with my game. Most golfers who start playing at age 66--as did--don't break 100 after three years, I think. I occasionally break 90. I took three 30-minute lessons, but the guy was all talk, no show. I get MUCH more by watching YouTube videos in which the instructor talks AND shows. People may say that I needed more than 1.5 hours to see results, but nobody I know who's taken dozens of lesson can break 90, and they've all been playing seven, ten, thirty years. The success--such as it is--that I've had happened because of Internet forums and YouTube videos, and several books by the likes of Ernie Els, Tom Watson, and others, and especially, I believe, from my willingness to think outside the box.
I watch Tommy Gainey strike his driver 290-300 yards with the left thumb wrap around the the handle like you describe standing behind him at a driving range
I seen every type of grip. If it works for you fine. don't assume its only for certain type of player and for certain clubs
I was referring to my stance, ball position, extreme rightward grips, and trying to feel square to the swing arc, not to the thumb out placement. I use thumb out for all clubs.