Good call my good man, that definitely makes more sense.
Would you think adding gypsum would improve things for someone in his situation?
Most definitely in every case. Kind of how you explained below, gypsum is not only good for some soluble Calcium but the fact that it pushes excess cations out of the soil.
In this case, probably mostly Na and K.
From my understanding gypsum supplies calcium sulfate, the calcium and sulfur easily split up; the sulfur will pick up bound up magnesium, and the calcium will pick up bound up phosphorus. And the way that gypsum releases it is available pretty instantly. Do you think this would create the calcium phosphorus energy you're talking about?
Something like that;
The Calcium and Sulfur will easily split yes. Whatever excess Cations are in the exchange capacity will be picked up by the Sulfur and the Calcium will be released in its place..The excess cation will stay attached to the Sulfur and will be washed out so long as you rinse your pot thoroughly, giving a good runoff.
Magnesium is actually the last cation that will be picked up and washed out as it's the heaviest cation. Potassium and Sodium are generally most readily leached by gypsum as their very light and mobile in the soil.
From what I've read, and I can find the sources if you'd like..
At a ph between 5-6 most excess Phosphate binds with Aluminum
At a ph between 6-7 most excess Phosphate binds with Iron
At a ph 7.1 up to 7.5 most excess Phosphate binds with Calcium
If you look at these elements (Alu, Fe,Ca) in their ionic form you'd see that they all have a +3 charge. Phosphate carries a -3 charge so if you think of it like a puzzle piece, The Phosphate and Aliminum/Calcium/Iron fit together perfectly. Making these complexes..
Another reason these complexes happen is because of the ratio of the elements in the soil. You'll always want to see a lot of Calcium so you're naturally going to see Calcium Phosphate binds which are like the glue that holds a soil together..
You're also always going to see a lot of iron in mixes these days as all organic matter has a lot of iron in it. Think of blood, what makes it red? Iron.. All my soil tests, especially when using basalt have had had iron especially when I was using 2-4 cups.. around 100/200 ppms.. way too high. I use 1/2 cup basalt per cubic foot now . It's plenty.
Aluminum, that's mainly coming from the use of alumina-silicates such as azomite, zeolite etc...you won't really see high aluminum if you don't use these things. If using fulvic acid I wouldn't use these silicates. If you're not getting your soil tested somewhat regularly i wouldn't use them either. You're ph needs to be above a 6.0 at the very very least. You don't want aluminum bonds breaking in your soil. Bad stuff