It seems that in 10.6.1.1005 update today the NoCheckVersion got broken?
It has been working so since the beginning of times:
path\Client.exe NoCheckVersion
allowed starting the client without starting the launcher first. This meant
(1) a bit less memory usage (no launcher)
(2) one less click
(3) but also if my intention was to start 2 clients I was able to do this right away; now you have to wait until launcher loads and only then start again or find the launcher in the quick-icons etc.
If the version did not match the server then you had to start the launcher to trigger updates. But otherwise life was simpler, faster. It's just a small convenience thing, but really, why remove it?????
(If you say was not a specified feature and so it is not a real 100% bug, then please consider this ticket as a "suggestion for a new feature". the suggestion being: please make it work again, make it possible to start a client bypassing the launcher, just as it has always been possible.)