At work people often ask for more "best practices" guides. In some ways this is sign of success: they're no longer begging for fundamental reference material and descriptions of basic use. Nevertheless I almost always wince:
1. "Best practices" carries an implicit sense of guarantee along the lines of "if you adhere to the best practices, then you won't run into problems," which is sort of difficult to assert with confidence, and is really a product design issue, not a documentation issue.
- It is really hard to make one-size-fits-all recommendations.
3. Best practice-guides don't address actual needs of users, or actual solutions to real problems, because they generalize problems and solutions beyond the point of re-usability.
This isn't to say that it's difficult or impossible to give recommendations, and indeed documentation is the best way that the purveyors of software have to to shape practices. However, the documentation should guide users towards better practices everywhere and isolating recommendations into certain types of documents is probably counter productive.
Onward and Upward!