What you need to understand is that the VO has 10, maybe 15 minutes to go through all your documents, understand your case and make a decision. Too many documents, especially unnecessary ones, not only makes it frustrating to the VO to understand your case, it may even confuse him. He may doubt your intent to study mistaking your excessive documents for your desperation to land in Canada. So although it wont do any harm (a VO may simply choose to ignore the extra documents) it is advisable to provide only those documents as per CIC's guidelines and keep your file as "to the point" as possible.