Pocket-sized guns are, indeed, viable. Finding one that I could sufficiently brace against important contact points, in my hand, to enable a repeatable grip, took some trial and error. Finding one that allowed a “natural” trigger finger placement, and a trigger stroke conducive to a smooth, steady movement, was also part of that trial and error. Actually, one of the first pocket autos I tried, the Seecamp LWS-25, was an excellent fit, but, I wanted more than .25 ACP, and, I worked for a PD that specifically excluded the carry of .25 ACP weapons, on or off the clock. The advent of the Seecamp LWS-32, and, later the .380 version, enabled Seecamp pistols being viable options.
A pocket gun need not be tiny. Careful selection of trousers may enable one to pocket carry a Ruger SP101, or Glock G19. Yes, I typed “Glock G19.” One type of uniform trousers, issued to me, in the past, enabled pocketing a G19. It was more a case of temporary storage, of a spare weapon, than carry, as my duty holster blocked access to the right pocket, and my radio blocked access to the left pocket, but, yes, I could tote a G19, on each side, if I wanted.
For a while, Wrangler Riata slacks enabled front pocket carry of Ruger SP101 revolvers. I believe that the front pockets have, however, become smaller, in newer-production Riata slacks.
Pocket carry can present some challenges, to achieving an unimpeded draw, ff seated, and/or if bent at the hips or waist. This is a reason that I tend to carry two weapons, for accessibility options, if one of the weapons is pocketed. Others may choose to move the pocketed gun to a more-accessible position, while, for example, seated inside a vehicle.