I'm a pretty decent shot with my S&W Model 36 snub-nose chambered in .38 Special.
I attribute that to the many thousands of rounds I have sent downrange,,,
With my (near identical) S&W Model 34 chambered in .22 LR.
I also have a Model 34 with a 4" barrel,,,
While it's a very nice gun with which to practice basic skills,,,
I do believe that the practice with the snubbie was more effective,,,
Than it would have been if I had practiced with the longer barrel handgun.
I think your idea is very sound,,,
Especially in these days of expensive centerfire ammunition.
All I can really say is that it worked for me.