Wow.. all those "hi-jacked" aircraft I saw during my time at Heathrow Tower that never got in the papers!!
I,m long out of date but know of no reason why crews should advise ATC other than to stop the smarty-pants in the tower telling them! I learnt this very early on when I told a departing Airbus that his gear was down. "Affirmative, we use them for the take-off" !!