Yeah, I LOVE Tropica plants, but nevertheless, none of that 90 step procedure (incredibly complicated) is necessary.
Plants that you buy from any nursery, including the Tropica specimens, are grown as if they were land plants. Most aquatic plants only live 1/2 the year submersed. In the dry season they are just like regular land plants. Their leaves and system of CO2 and nutrient uptake is very different when they are in air. In nature, the wet season, or flooding in general is a gradual thing. The average water level rises slowly, giving the plants time to make the adaptations to life underwater.
In your tank, you will flood the level in a few minutes, never giving the plants the opportunity to make adjustments so they are traumatized. Air breathing mechanisms get flooded and the plants has to make a rapid adjustment. That's why nutrients and CO2 have to be provided in large quantities.
These land grown plants have been "fattened up", because their life in the nursery is very easy. They buildup starch reserves and can survive for a few weeks on their stored energy reserves. That's probably why the philosophy of not dosing for a few weeks comes from. Furthermore, many people are still under the false impression that adding nutrients to the water triggers algal blooms, so they try to be as careful as possible about adding nutrition to the water. Those instructions are playing into the fear that has carefully been built into many plant care products.
People get algal blooms all the time at tank startup because they always use too much light, assume that their CO2 is in good shape and they do not pay careful attention to flow and distribution. Then they blame the algal blooms on nutrients. This misconception is all encompassing and pervasive. The manufactures responsibility is to inform, but it's easier and more profitable to feed the fear, especial if the advice is consistent with the ideas that generate the common fear.
When you know the truth, and when you understand that a high nutrient load neither causes algae nor is toxic to fauna, then you will realize that it is in the plants best interest if maximum nutrition is provided. If the hobbyist uses excessive lighting this causes a huge CO2 and nutrient deficit. The plants will use up their reserves of starch and very quickly go into energy debt BEFORE they have made the physical and chemical transition to survive underwater life. They become weakened and algae attacks. Algae do not care about nutrient levels in the water column.
In a tank the presence of plants affects the behavior of algae and the presence of algae affect the behavior of plants.
So when you start a tank you should always think about arming your plants against malnutrition because that is the real cause of algal blooms, NOT the presence of nutrients in the water.
Fear of nutrients is a powerful psychological barrier that causes the demise of many planted tanks.
Could you also provide some explanation for why an established filter should not be used when setting up a planted tank?
Again, the origin of this advice is rooted fundamentally in another primal fear, that somehow, if you use detritus from another tank or another filter, then it may be contaminated with pathogens and/or algal spores, and as a result, you may introduce these pathogens into your tank.
This is yet another illusion. There is no way to preclude the introduction of pathogens and algal spores into your tank. They come with the fish. They find their way into the tank by spores or other airborne vehicles. Every tank has pathogens and algae. If the fish are kept healthy then they are not bothered by these agents. If fish are exposed to shock or trauma their defense system is weakened and a pathogen will attack. It doesn't matter whether the filter material had pathogens in it or not.
Using detritus from an established tank or filter is an excellent means of seeding the new tank and filter with beneficial bacteria, but vendors would rather you buy their frozen zombie bacteria vials at hideous prices instead of your obtaining bacteria for free.
Cheers,