Yury Tarasievich wrote:
This one of five pillars, how is it enforced, exactly?
It's important, but it's not one of the five pillars. In fact the rule mongers try to expand it to well beyond it's original intent. If it can be verifiably sourced it's not original research.
Many a vocal "defender of faith" feels safe to put forward one's own perception, oft mythologised, as a basis for contention of "unconvenient" sources, no matter how fundamental.
I had this impression that sources are to be countered only by other sources, not by somebody's own claims?
Yes, but some would be amazed by that idea.. ;-)
And if not countered, sources fall under the NPOV policy — all major academic POV are to be represented, with balanced language?
Sure, all major POVs (not necessarily academic, and some minor ones included too) are to be includible. Balanced language does not mean that all POVs get a balanced amount of space. Having only one POV is common in the early stages of an article. The absence of a differing POV (assuming one exists) is not an excuse for removing what's there; it's an encouragement to add the missing material. If a differing POV exists, and you know that it exists, it would not be very fair-minded to insist that material be deleted.
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