I hope my reply is not taken the wrong way, i recognize you are en expert.
No, I think folks take things the wrong way personally, it's not.
It's an open debate, folks are always welcomed to ask questions, support their views and look into the issue further, the goal is to learn more about it, not to be "right or wrong" for one's ego. We all seek the same thing, what is really going on and why, how etc.
So we all have the same goals.
You might refer to me as an expert, but I have not thought of myself this way at all, I'm wondering many things and have unanswered questions myself and need to be sure of what I think it going on, so I have to think of other ways to make sure I do not come to the wrong conclusion.
I have to confirm and test, look at the research and make sure it does indeed apply or not. Then ask others who have done the same etc.
I cannot just look and know
This way I can reason through it much easier, I might not know exact causes etc, but I can at least rule certain things out stepwise by tedsting what the most likely candidates are.
Then I'm left with only a few things/choice of what it might be, it might be 2 or more, it might be only one thing.
This way I can know what the differences are between pH, KH, nutrients in soil vs the water column, submersed sediments vs terrestrial etc.
You have to pick it apart to get at the root issue.
This has nothing to do with you personally, nor is in any way a negative critique towards you. It's the idea, not the person that's being debated.
When things turn personal, as they often do on the web, then you stop learning and just get pissed off. I could never do this for very long if that was my gig. In person, such debates come across very different, there's fast feedback and you can tell that the tone is very different than what you might assume on line text to be.
Instead, look for evidence to support your view, or learn more and change your view if you think the idea is valid etc. Convince yourself that it makes sense
in other words. Heck, we all make bad assumptions and mistakes, that's how we learn actually. So we try and help others not repeat them and discuss the issues in depth. Everyone is the same here.
And do not be afraid to challenge anyone, as long as you have a good "on topic" leg stand upon. Many pull this baloney where they inject doubt into the debate and suggest impossible methods/test that no one will ever do just to corner the other guy, an example is intelligent Design Debates, and we have our share of folks that keep going on and on ad nauesum claiming say "NO3 at 20ppm causes algae:", then when that was disproven, they suggest this causes stress to fish, and then when that was shown to be false, they then go after shrimp............. and then when that was shown also to be false, they cook up some long term monkey business about health etc, but cannot ever test these issues themselves curiously, then they claim it's only he high grade Crystal Red shrimp that are having issues with high NO3...........well, now we have certainly narrowed it down to a few hundred folks keeping high grade CRS, not some generla baloney, even if we never answer their question.
We have to have some degree of reason to assume risk.
Others will try to attack the methods and claim it's not "research grade test", and keep carrying on and on about that part, but if you add something and it does not induce algae many times, it's a wide spread observation, we can repeat it, then that really does not matter. We can still see if adding PO4 causes algae or not or what occurs at higher KH's. We have a control tank to show that the system is independent and there is no affect on the fish, algae, plants etc.
All you need a re few folks with high KH's growing plants just fine at higher pH to disprove the hypothesis.
Then the other issues with the methods no longer matter, you KNOW the KH is high etc and that you have good growth, so with other tanks, then you know it must be another reason that the plants are not growing well, not pH/KH.
Folks have a bad time with growing plants for many many reasons, so we need to look at successes where they have FALSIFIED the hypothesis put forth.
If you think that something causes an affect, then we should be able to repeat it. If PO4 excess at 2ppm causes algae, then I should be able to see it and add PO4 to an otherwise algae free tank and get algae.
No need to do research and make a big deal out of it if the pilot study never shows much promise
You can read the hydroponic methods and other container nursery production water issues in a wide range of text if you are interested.
Then you gain from this and have a better understanding. Which is pretty much why we talk about this stuff!