This is correct, its not needed for good performance, and most things websites require cookies for dont require the disclaimer, with two caveats. First its pretty clear from the law what requires it, but what if you are wrong, what if corp requires legal to sign off on the engineers statement that it is legal, its not like you gain much from not having the disclaimer, and second, most freemium analytics (e.g. googles) and all ad related services do require it.