The authority is that the IFAB instructed The FA on how interfering with an opponent should be adjudged. They were clear that where NARs were used, that was the interpretation they (IFAB) wanted using. You don't "feed back" to the IFAB, you do as you are told. If a game has NARs appointed, then the latest interpretation will apply. It's very simple to get across to the players ... play to the whistle.