I think there's a 5th force: long-term editors who believe that they need to/can/can only counter particular editing behavior by altering the policy.  This is exacerbated by their apparent utter unwillingness to see that the effects of the policy they insist upon go far beyond correcting the unwanted behavior.  (They also are or become blind to the fact that the objections raised are due to this unwarranted and disruptive side-effect.)  Actually, the policy probably almost is ineffectual against any behavior: the policy is invoked when the long-term editors challenge the edits.  That the policy says anything about source (or material) types is scarcely noticed by those doing such edits.  We can be virtually certain that any policy wording can and will be used/misused by those with an agenda.  Policy needs to be crafted very carefully.  The overal Wikipedia policy includes "Be Bold" and "Ignore All Rules."  The overall policy was crafted very wisely.

It's also true that, not seeing the supposed offending edits, we can't really be sure the edits were improper.