Improve docs

DOCUMENTATION.md

@@ -201,7 +201,7 @@ If you want all the details, here they are:
 * Open `Faqt.AssertionHelpers`.
 
 * If needed, open `Faqt.Formatting` to get access to `TryFormat` (described below) and `FailureData` (mostly useful for
-  higher-order assertions).
+  higher-order assertions as demonstrated above).
 
 * Implement the assertion as
   an [extension method](https://learn.microsoft.com/en-us/dotnet/fsharp/language-reference/type-extensions#extension-methods)