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I also want to say that I'm not necessarily arguing against MOND here. I really like the work done by Stacy McGaugh et al. But from a more cosmological point of view, I see a lot of support for CDM. (And more than just TV cosmologists agree with that.)

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I look back to where this started, and this started with Fritz Zwicky noticing that galaxies and galaxy clusters are moving faster than expected. This is the root observation.

From there, a good question is "How do we model it?". And sqrt(GM/R^2 * cH/(2pi)) works really well.

By the way, cH/(2pi) = c^2 / (2pi * 13.8 bly), which looks like centripetal acceleration.

Galaxy rotation curves are really not the root observation behind structure formation though, those are two very completely different things.

I'm also struggling to find what MOND has to say about all the astrophysics observed that LCDM people try to model to get their Tully-Fisher to work. If MOND is true, why would all these astrophysical feedback effects (such as supernovae) not matter for Tully-Fisher?

The root observation is that galaxies and galaxy clusters are moving faster than expected, and holding together more strongly than expected.

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