After listening to numerous cut glass accents sharing reminiscences of Prince Philip, I am pondering use of "one".
Growing up in Ireland, it would have been seen as anglo-posh bordering on the comic. But now I am thinking about it, the French have "on" and the Germans have "man", and it does fulfil a useful role. I feel Prince Philip's cronies overuse it where "I" would suffice, but there are times where I would like to use it, but...I just don't think I could!
English people, can you say it and sound natural? Is it something that will become less and less common until it dies out?