Well...the intention of my original post was not to ask for your personal opinions and experiences.
It was:
Is anyone aware if airlines have (written) guidance for their employees regarding this subject?
Until now no one of the replies was able to say yes or no... .
Instead professionals (?) took things personal (... why then?).
To the high tier passenger:
Of course everyone gets on board before flying, but if there is already an entry order, it should be made clear, who keeps for the whole thing running. Even if one has no pax tier at all, he/she should be treated as a paying (!) guest.