Eddie Mair was the epitome of what good BBC news interviewing and presenting should be like (with a wicked sense of humour as a bonus), and clearly not one for self-publicity or remit expansion, so when he felt it was time to move on after a whole career there it should've rung big alarm bells

That was an interesting one. Certainly an excellent journalist, though it's not clear to me what the reasons for the move were. It may have been that he wanted more freedom to say what he liked, in which case the BBC was right to say "ok, thank you for your service"