Hmm where does it say this?IF you READ the CIC website you would have seen that Proof of Funds is not a requirement for CEC applicants however if you as the applicant believe it will be helpful to your case then you can include that additional information.
I looked here and it says "You do not have to meet the funds requirement if you were invited to apply under the Canadian Experience Class" and only that "you must upload a letter explaining either that you have been invited to apply under the Canadian Experience Class". Although even that seems strange that you would have to tell them
So nowhere there does it say providing unnecessary information will help with your application