A researcher-friend recently complained to me that her research paper had been rejected, because the reviewers considered it “boring”. I recommended that she complain to the editor-in-chief of the journal, because in my book, “boring” is no acceptable reason to reject a paper. (“Trivial” may be, but that is a different issue.)
The reasoning behind rejecting a paper, because it is “boring”, is as follows: Research should be novel and provide new and perhaps even unintuitive insights. Results that are not surprising (in the mind of the reviewer, at least) are not novel and therefore not worthy of publication.
That’s not science. “We have long known this” should not be an argument to deny publication of results that have not been shown before using appropriate research methods. Expert opinion is input to science, but not science in itself, and cannot be used as a replacement for thorough research.
So, if a (real or self-proclaimed) expert argues, “everyone knows this”, object. “This” can count as known only if it has been shown in a person-independent way using appropriate methods. If we were to accept expert opinion in lieu of solid research, we would undermine an important quality criterion of science (objectivity or researcher-independence of results).
Medicine has a nice play on words that applies: Medicine used to be “eminence-based”, but it now wants to be “evidence-based”. That’s what software engineering should be aiming for as well.