I disagree and think that you are trying to work within too narrow a definition. There can be fine line at times between ROS and Past Medical History. Review of Systems is defined by CPT as “an inventory of body systems obtained through a series of questions seeking to identify signs and/or symptoms that patient may be experiencing or has experienced.” This definition does not just include current symptoms, but also symptoms that may have occurred in the past.
Documentation Guidelines state that the physician should be given credit for "positive or pertinent negative responses." Physicians commonly document pertinent negative responses with the term "patient denies" and frequently add "history of" as a way of saying anytime in the past. The physician is not obligated to ask about all possible symptoms for each given system, instead they are only required to query the patient about specific concerns they feel to be pertinent to the patient's presenting problem. The physician is also not obligated by any of the existing rules to specifically list positive findings. As a result, any given ROS documentation may reflect only pertinent negatives.
Simply using the term "denies history of" should not exclude the statement as ROS. Statements such as "denies history of frequent diarrhea," "denies history of joint pain," or "denies history of vision problems" whould clearly be ROS in my experience.