When you ask a question like:
What's the best way to do "X"
The preview/editing engine in SO warns you that this is a subjective question and is likely to be closed. Which makes sense. My guess is that it sees the word "best" in there and assumes it's subjective.
However, I'd argue that a question like:
Best practices on doing "X"?
is not subjective in instances where it's been established what the Best practices are on something and the question is asking what those are (and the question will act as a reference for others).
And these questions tend to not get closed so I'd say improve the parsing (assuming I'm right about it) to warn if it sees "best" but not if it sees "best practices"
EDIT: ok, so this question was unpopular. That's fine. But it occured to me that my original point was lost so I'm going to add this and drop the subject.
SO has a tag called "best-practices". And yet, if you ask a question with the word "best" in it, you get this message which, while it doesn't necessarily mean your question will be closed, is potentially confusing to users since you're fine with asking about best practices but are getting on to them anyway.
That was my point. Not whether or not you should be asking those questions, but rather that it might confuse or annoy some users that you're fine with them asking best practices questions to the point of having a tag for it, but are going to nag them anyway.