Allow me to add one more thing to this thread - I completely agree with the longer lines are better statement, but until such time that someone is able to procure those lines, here is how you should approach the 'turn down to serve' method:
Carb at whatever PSI you want - i.e. 12 PSI
When you are ready to serve, turn your gauge down to serving pressure - i.e. 6 PSI
You must then PURGE the keg of it's pressure until you hear gas flow and re-check the gauge. You may also need to do this here and there throughout your serving day.
At the end of your serving day, turn gauge back up to 12 PSI.
Why do you need to do this? Once your beer is fully carbed, you have a lot of liquid that is holding 12PSI of CO2. The headspace is equal to that 12PSI. When you turn that gauge down, the headspace is NOT vented (in my experience and knowledge). After pouring a beer or two, it will probably get down to your serving pressure, but in order to avoid a glass of foam, the purge will help. Once this headspace is at 6PSI, it is no longer holding the CO2 in the beer. The beer begins to degas until the headspace is once again at equilibrium with the beer, maybe 11 PSI if you've got a full keg. This takes time, but will eventually require another purge to reset to serving pressure.
The above is also how you can go about bringing an overcarbed beer back down to the right CO2 level.
Moral of the story? Longer lines = win.