The act of carrying a concealed weapon comes with a measure of responsibility. Part of that responsibility is ensuring that you're as properly trained and equipped as possible. Carrying a Walther P22 says neither in my book....
dude, easy.
provided that
A.) your P-22 has proven to be reliable
and
B.) you can't reasonably carry something better
there is nothing wrong with doing so. people will make the same remarks about 9MM, .40 or anything else the deem not to be effective enough.
you should really do some research on how many people .22's have killed. but it's not about killing, is it? it's about stopping the threat. If your threat didn't at least slow down with 10 rds of .22 in thier upper body, then you are doing something wrong... aka, you prob never should have drawn in the first place, because sometimes running is just a better choice. but, if I need to shoot and run, I am betting that those 10 rds of .22 are going to cramp my attackers style.
there are about 100 scenarios where carrying a P-22 is about worthless, and might actually make things worse for you.
there are prob another 100 scenarios where it could save your life.
the single most important aspect of CCing is not the tools you carry in your pocket or on your hip, it's the tool you carry in between your ears.
with all that said, a few caveats...
I don't carry my P22 frequently. more often than not, it's the XD-40sc. really, they are about the same profile size, the XD is just bulkier.
I would never carry anything but a spotlessy cleaned and lubed P22. they do get real finicky when dirty.
I would never carry the P22 with "value pack" ammo.
I have broken all of the above rules at least once. Really, something is better than nothing. or why else would some of us carry knives when that's all we can?
btw, I find even the 3.4" P-22's to be stupid accurate. last week I was hitting clays at 75yds 40% of the time, and the other 55% of shots were falling within 6", with 5% being wild but still in a "man sized" area.