On another forum it was asked whether authors should “push the grammar envelope” and embrace the singular plural. I think the wrong question is being asked when you ask whether authors should push the grammar envelope for two reasons: First, because it ignores the purpose of grammar, which is to ensure that there is communication between author and reader. Second, because to push the grammar envelope assumes that there are firm rules to be pushed. The first reason far outweighs the second, but neither is ignorable.
Regarding the singular plural, it is neither pushing the envelope to use it nor a violation of a firm rule nor a distraction from communication (in most cases; there are cases in which it is clearly wrong because its use is confusing). In other words, I think that editors, writers, grammarians, usage gurus, etc., make the proverbial mountain out of the molehill when they oppose the singular plural.
Consider what makes a great editor. A great editor is someone who ensures that a reader understands the editor’s author; that is, ensures that the reader does not leave the book thinking the author is in favor of, for example, genocide, when the author intends the contrary. An average editor can cite chapter and verse of why x is not to be done, but cannot explain why doing x makes the author’s point unintelligible. The amateur editor either blindly accepts the singular plural or remembers having been taught that the singular plural is incorrect and thus blindly changes it.
However, if the singular plural is incorrect, it is incorrect because it makes the author’s point unintelligible, not because a group of self-appointed grammarians have written that it is wrong.
English is difficult enough without making it impossible. Editors constantly twist and turn to apply “rules” of grammar in the mistaken belief that there are rules of grammar. What are too often called rules are really current conventions.