Where on Earth did you here that it takes roughly 4 weeks? It could take a day for you, or a year for you. It will vary. But that's were the practice comes in.

I agree with Iamerik, experiment to see which method is right for you, and don't get your heart set on just one.

As for how many times you should do an RC, do it whenever you see, hear, etc. something out of the ordinary. Doing it that way usually works better than RCing every something minutes.