Yeah, you googled "articles that say what I want to hear" and you've found some, and did not really understood what they say. Congrats, I will definitively change my mind now.

But obviously, you "forgot" the articles that don't go in your direction, such as https://onlinelibrary.wiley.com/doi/full/10.1111/j.1756-5391... (which is easier to find than one of the articles you quote, so you probably either did a search that target specific articles, or saw it and choose to ignore it). This is a meta-analysis (so it is not just one study), and it concludes that per-level classrooms does not improve high performing students while improving the low performing students. In other terms: it says that non-mixed classrooms will drag students to the bottom.

> And yeah if I'm producing better results, I'm going to go ahead and characterize myself as having more expertise, evidently.

You DON'T produce better results, you had ONE student, this is way not enough to conclude if you are producing better results.

> Your claim, basically, is that putting my child in a group of kids that is operating on a level several years beneath her somehow benefits her.

You said yourself that the class contains a big fraction of kids that are better than her (and, yeah, I know, you don't believe the experts, your kid is in fact sooooo smart). Even if your kid is smarter than them, it is a lie to pretend that your kid is in a classroom that has a level which is several years beneath her.

And again, a naive non-expert would have a naive intuition: "oh, if some students are not at her level, of course she will not learn as much new stuff at her level so of course it is not good". Experts know that this reasoning is naive: learning is not just force-feeding books in the kid's brain, and what works with kid X may not work with kid Y. At the end of the day, if what you were saying was true, it would be clearly evidenced in data. But it is not. Even if you can find some articles where they say high performing students in non-mixed classroom did a bit better, how do you explain that there are so many studies that say they don't see the clear gap that your reasoning implies? How do you explain that? Let me guess: they are all communists part of the strange conspiracy because they are afraid of how smart your daughter is.

(by the way, do you realise how stupid your argument is: neither me or my kids will ever have to compete with your daughter. And competition is not even about high-performer or smart people: the smart people often end up being uninterested in the stupid egomaniacal competition, they prefer fulfilling lives. The fact that your daughter is smart does not make her a threat to anyone, and if she is smart, the fact that she was in a non-mixed classroom will certainly not impact her opportunities. If it does, I guess it means she is not really as smart as you think she is)

This is yet another "armchair scientist" approach: in science, we know these kind of intuitions are very risky. You fall for it because you are not an expert, you are just a self-entitled "Karen" who got confirmation bias that they know better than everyone.

Again, maybe your kid (and the handful of your "social network") is one of these outliers who thrive in home-schooling or non-mixed classroom, but it does not mean it is true. It does not mean your "genius idea" is not something totally bad to apply.