The thing with the aquatics hobby is that there is more than one way to skin a cat. Everyone will have their own way, and opinions will differ on the proper way of doing things.
With regards to how much ammonia to be dosing, a moderately stocked tank will be producing 1ppm ammonia over a 24 hour period. Dosing to 2ppm and having it cycle out within 24 hours will mean your system should be able to deal with any short term ammonia spikes if you moderately stock. Dosing to 4ppm will mean you can safely more heavily stock. Me personally, I'm happy to dose to 1ppm and then lightly stock when it is cycling out within 24 hours, then build up stocking slowly over a few months. Never had a problem with this.
It all depends on how cautious you are and how heavily you plan to stock. I would say, unless you plan on stocking really heavily right from the start, 4ppm dosing is overly cautious.