This comment perfectly encapsulates the point that I am making about best practices: the concept is used as a cudgel to silence debate and to confer a sense of superiority on the practitioner of "best practice." It is almost always an appeal to authority.
No one wants cowboy pilots ignoring ground control. Doctors though do not exactly have the best historical track record.
Knowledge communities should indeed work towards consensus and constantly be trying to improve themselves. Consensus though is not always desirable. Often consensus goes in very, very dark directions.
Even if there is some universal best practice for some particular problem, my belief is that codifying certain things as "best practice" and policing the use of alternative strategies is more likely to get in the way of actually getting closer to that platonic ideal.
Perhaps a better example might be "covering indexes," or what Oracle would call an "index full scan."
Is is an idea so efficient that to disregard it is inefficiency.
"I had never heard of, for example, a covering index. I was invited to fly to a conference, it was a PHP conference in Germany somewhere, because PHP had integrated SQLite into the project. They wanted me to talk there, so I went over and I was at the conference, but David Axmark was at that conference, as well. He’s one of the original MySQL people.
"David was giving a talk and he explained about how MySQL did covering indexes. I thought, “Wow, that’s a really clever idea.” A covering index is when you have an index and it has multiple columns in the index and you’re doing a query on just the first couple of columns in the index and the answer you want is in the remaining columns in the index. When that happens, the database engine can use just the index. It never has to refer to the original table, and that makes things go faster if it only has to look up one thing.
"Adam: It becomes like a key value store, but just on the index.
"Richard: Right, right, so, on the fly home, on a Delta Airlines flight, it was not a crowded flight. I had the whole row. I spread out. I opened my laptop and I implemented covering indexes for SQLite mid-Atlantic."
This is also related to Oracle's "skip scan" of indexes.
Best practice doesn’t mean you’re at the mercy of the consensus, it just means you have to justify why you should stray from it.