With other events going on in other threads I have sadly neglected this thread.
In a way that's fine because it merely shows that everything went well.
Kong Frederik har selv skyld i, at der er kommet en mere afslappet holdning til, hvordan de kongelige skal tiltales, mener flere eksperter i B.T.-podcasten 'Kongehuset bag kulissen'.
www.bt.dk
Here is a BT article about the use of informal and formal you, and the informal style by FX&QM.
It stems from an enthusiastic onlooker in the town of Vejle saying to King Frederik: "Du er en dejlig steg! = You're a hot dish!" Using both informal you and a very free compliment. King Frederik reacted with a smile. - No scandal or offense taken by anyone but a few I think.
In the article you will see a poll, which is not particularly serious in the way it is phrased and also because I think the segment reading newspapers are mainly counted among the 30+.
Anyway a majority believe it's perfectly OK to address the royals with informal you, while a minority 44 % believe formal You is more appropriate.
Personally I believe that the de facto abolishment of formal You, means the language has become poorer. The usage of formal You in a number of situations is a useful tool. You can for example address someone in a stern manner while using the formal You, which means you still maintain a level of respect and the meaning comes across as much less rude.
I certainly, firmly and absolutely believe that use of formal You should be used when addressing the leading people in a society, like the PM, Chairman of the Parliament and adult members of the DRF. Simply as a way to show respect for the office.
And also in a setting where the Royal show is on, there I certainly believe formal You should be used.
However, if it's at a school outing, or King Frederik is picking up a child from handball or you are talking with Joachim about engines at a race, there I think it would be more natural for the conversation to use informal you. Or at least it makes no big difference.
Having said that I simply cannot remember the last time I addressed someone with formal You in Danish. I did when I was in the army because that was the regulation back then, but apart from that I simply can't remember.
My wife does on occasion when dealing with elderly who still prefer formalities, or when having a work-related argument with a relative of a client who has stepped out of line. (Gone Karen on say a care-worker.) That's where her annoyance or the seriousness of the situation is emphasized by using formal You.
ADDED: They were lucky to finish the cruise yesterday, because we are having a minor storm here right now.