I think there are different ways to run reef tanks and they may be such different that they are really hard to compare.
This doesn't make sense when nutrients are in surplus. Nitrate levels of a few ppm are already so high that ratios don't matter any more, it is just more than enough, the uptake is saturated.
It is like putting a huge table with food in front of you. Can you eat more just because there is more food?
I have always used urea because it is a non-toxic form of ammonia. There seem to be some other reduced nitrogen compounds, some amino acids, that give an even better effect, at least in combination.
We (Tropic Marin) have just released a product that supplies fine water insoluble phosphate particles. That is my preferred phosphate supply. I am happy that I found it.
Why don't you do it like Claude Schuhmacher recommends in the video? Look at the corals, the corals don't lie.
At the moment I don't have any target levels. I didn't have nitrate target concentrations the last 20 years, only observed phosphate. At the moment I largely ignore any parameters and don't test. I just want to watch, observe, see what is happening without even being influenced by some parameters I may have found.
In my eyes preset "target levels" is the wrong approach. Look what works, and when you think it is good, these are your target levels. Corals don't lie.
If you ask me for the concentrations I would recommend, 0.1 to 0.15 ppm phosphate, and just ignore nitrate, it is not important.

Dose trace elements in certain ratios, try to achieve nitrogen limitation.