Yeah the high carb, shake, carb, shake, is for when you're in a pickle and need to get it carbed fast. You're essentially trying to get as much c02 in the beer as you can as fast as possible. It does work, but you usually have more problems than worth it. I've been pressed for time with BBQ's and events etc. and had to carb fast, I usually just do what Yooper said carb high for a while, release, carb lower, I tried the shaking thing, was a mess trying to get it back to a normal carbonation level without foam. Obviously best way is to be patient and carb at 12-20 over a longer period of time. Pour a glass or two here and there to where it is you like it then put down the pressure for serving. In a pickle, put it on higher PSI (40'ish), but you will have to play around with it to have it pour right. Another thing to add, sometimes poppits and picnic taps can leak, i've had a chest freezer full of 5 gallons of beer (yeah I cried) so I tend to not even put the beer line on until after 10 days or so and you have time to watch it every now and again to see it is not leaking. It'll take some time to figure out your system and you'll know the right levels for your beer lines and set-up, take some good notes on what you did with the previous keg and the results and you'll get it just right. Trust me, I love kegging but hated all the foam I was getting until I got it all figured it out. I wouldn't worry about c02 being left on, put your keg on 12 psi in the evening and if it is not empty the next morning, then you probably don't have a leak and you'll be fine. And unlike Golddiggie, I had a busy summer and did not brew too much so i'm with 2 half kegs and zero pipeline, so don't worry about it. Time to brew!. Goodluck.