• I like the merge with examples, keeps the navigation bar tidy.
• The changes for {index, assertionScope, about}.md might be out of scope for this PR?

I generally like the wording changes for examples.md.
Are you aware that only the sections Assert, StringAssert, CollectionAssert and all but one example from Exception are migration from MSTest?
The remaining sections are examples on more idiomatic use of Fluent Assertions.

The changes for {index, assertionScope, about}.md might be out of scope for this PR?

I wanted to show my idea in-context though and felt this was the best way to do it. Since your PR to upstream should probably be squashed a bit, I submitted fluentassertions#646 with my changes to make things easier. I would recommend abandoning this PR and you just making the appropriate changes to move things (as inspired by this) on your own branch.

Are you aware that only the sections Assert, StringAssert, CollectionAssert and all but one example from Exception are migration from MSTest?

Nope, I was not 😀 I was admittedly kind of confused by the "Best Practices" title when I saw it showing changes between assertion libraries.

I'd recommend splitting these two things to avoid this kind of confusion. In that case I'd perhaps keep the MSTest ones under examples and have a Tips page that can be about how to write better FA assertions.

In all cases, I would avoid the "old" vs "new" terminology. Given the potential connotations, I think that would only be appropriate if documenting changes between FluentAssertions versions.

Thanks for all the suggestions, they are now included in 930df67