trend was holding handguns horizontal rather than vertical ... never understood it unless maybe some thought it looked cool.
There is definitely no compelling strategy for holding firearms other than the designed/engineered way!
Is there a point to this that fits in this forum?
Consider this.
When our defensive shooting instructor who taught local PD/SD SWAT teams (Who was also our USPSA RSO) taught us defensive shooting including unsighted point shooting (He told us he didn't want his SWAT students to break eye contact with their targets who were often moving fast under low light/visibility conditions), we asked about "gangster" grip and shooting two pistols at the same time.
He laughed and showed us all the ways why shooting guns sideways or two guns could be problematic from lack of accuracy, brass to face, brass from left hand hitting right hand/arm, potential for jams, etc. He did say, as he taught us unsighted point shooting and checked us off on fast sighted point shooting at 7 yards with 4"-6" pass/fail criteria, to choose the shooting method/stance/grip that we wanted to use and practice until we reached proficiency to perform with strong/weak hand consistently (Outline of training on this post) -
https://www.thehighroad.org/index.php?threads/flinching-drills.864546/page-2#post-11416785
Few years later when I was shooting USPSA at another range where I was learning stage design and setup, when the guy who did stage design/setup (who also shot IDPA) began to incorporate more and more cover fire shooting situations, shooting prone under cover and shooting one hand (strong and weak) around barricade (Not to mention non-linear sliding targets, bouncing targets behind window opening, waving targets behind cover to all mimic bad guys evading and returning fire).
If you're under fire and hugging the ground, you can get lower if the long magazine is sideways.
So during our all day practice range sessions using mock/previous week stage set ups, we seriously approached best ways to engage each types of these "hybrid" targets (We were shooting up 1000-2000+ rounds each during these long practice sessions). What we found during single strong/weak hand shooting around barricade was holding hands at more natural canted 10-2 O'clock driving position on steering wheel, especially "torqued" forward better locked the wrist to provide better support. And when we practiced shooting prone under barricade with about 4" opening to not allow traditional vertical shooting, shooting with ejection port down kicked up dirt/dust and ejecting cases would bounce off ground while shooting with ejection port up did not. And for laughs we tried two pistol shooting and holding 10-2 canted shooting positions allowed ejecting brass from left hand pistol to drop towards the ground.
Since then, whenever I saw shooters doing the sideways "ganster" shooting at the range, I use that as an opportunity to show them different shooting methods/positions/grips starting with benefits of 10-2 O'clock canting of single hand shooting to superiority of two handed modified/relaxed isosceles stance ending with fast sighted (Looking past the front sight) point shooting at multiple targets with double-taps on each target as demonstrated at 1:55 minute of video on this post -
https://www.thehighroad.org/index.php?threads/trigger-control.834737/page-2#post-11245649
Everyone of them became fast learners and they invited their family/friends for subsequent range sessions to learn the ways of "Zen" of shooting (Absolutely being able to produce holes anywhere on target at will fast) as broken down analysis of Jerry Miculek in this post with utmost trigger control -
https://www.thehighroad.org/index.php?threads/trigger-control.834737/page-2#post-11245640
I lost count how many people I "shared" defensive point shooting with over the decades but now include demonstration of single hand canted shooting but with added feature of using just thumb and third finger to demonstrate control of firearms (9mm/40S&W/45ACP) even with weak grip but well practiced grip and trigger control can produce accurate shots on multiple target and have them return demonstrate to shatter that notion out of their minds and to give them confidence over their pistols.
Recently, I cut my 100 yard 22LR testing short when father/son new to gun ownership showed up and was waiting for me to finish shooting. They were curious about what I was doing as I had rifles taken apart on the truck tailgate as I was swapping out 10/22 bolts and as we chatted, father wanted to teach his teenage son how to shoot but having taken only one shooting class, father himself was just learning to shoot.
I stopped shooting and pulled out my Glock 22 and swapped out the slide with Advantage Arms 22LR slide and proceeded to teach them 4 hour defensive point shooting to include strong/weak one hand canted shooting (See bottom of post) -
https://www.thehighroad.org/index.p...22lr-on-the-cheap.898035/page-2#post-12183064
By the end of the session, both father and son were shooting fast 4" sighted point shooting groups at multiple targets placed at 7 yards using modified/relaxed isosceles but also practiced shooting strong/weak canted one handed. They couldn't believe what they were able to do in just one session and promised to practice quick draw dry fire (to not move the front sight/muzzle) and magazine change while watching TV until the next range session (To be joined by their family/friends).