the ed tutorial is pretty much the basic carpeting technique, and the one that pvaudio have illustrated in his tutorial is a more advanced technique, where you can create the dual carpet tone look.they are both widely used in the car audio seen and nether is really better then the other.
depending on the particular goal for the final product look one technique will be used rather then the other.
when you're in business to make money, you use the fasted technique that will get you the results you need.
if you're going for the one tone carpet look. then use the simplee carpeting technique to get the job done since is faster, and looks good.
if you're going for the two tone technique then use the recessed cut on the sides technique, which will allow for the use of two carpet tones and enhance the look of it as well.
all these techniques have been around for a long time. and if you look closely to the builders carpeted enclosures, you'll notice that they have been implemented for a long time. and that none of them have been invented by them or resently. you just use what ever technique applies for that particular enclosure and call it a day.