When one uses Anecdotal Evidence information as the bases of a design decision, it becomes Anecdotal engineering. True engineering is based on facts and accounts for all of the variables which have been fully identified and understood. It's science based. Carefully test are involved such that there is only one variable is in question at any time. AKA the scientific method. Solid engineering result is the product that is guaranteed to work as advertised. Following anecdotal evidence based advice alone can potentially not solve the real problem at all. It may change it, mask it, or even lead one into having more problems leaving you more lost then ever. You must understand all the issues first for only then can you truly determine what the best advice is.
Best Practices is the best advice simply because it is based on a full understanding of all the issues such that the recommendation will work for everyone every time. Not just some of the people some of the time. Best practices has engineering and science to back it up leading to become sound advice. Stated another way, Best Practices is all about doing something right the first time so you do not have to go back and fix it latter. It gives consistent and repeatable results.
To see what are the best practices, go to this section: DCC & General Best Practices