Controversy raged last week over the issue of whether or not the Princess of Wales has regularly been called “Katie Keen”. In Endgame, his new book about the royals, Omid Scobie claims she has. Her “pliable” and “coachable” approach to royal duties led, he writes, to the nickname “Katie Keen” becoming a “popular refrain on social media for several years”. Tuesday’s Daily Mail disputes this: “A search of social media last night… found no mention of the moniker before it appeared in the book.”

So what’s going on here then? I must say, to my ears “Katie Keen” doesn’t have the ring of social media about it. Where’s the antisemitism or Islamophobia? Where are the makeup tips? Plus I’ve never heard her called that. Still, it’s not beyond the bounds of possibility. But the Mail’s view is clear: the disgraceful Scobie, relentless advocate of Meghan and Harry’s cause, has made it up as a vicious slur. How dare he call her keen, thinks the Mail, and suggest other people have also called her keen?!

Scobie and the Mail are at loggerheads but they agree on one thing: it’s not nice to be called keen. Keen is an insult and the notion of her being keen undermines the Princess of Wales’s image and makes her a less suitable person to go around opening things and shaking people’s hands.

The question this weird consensus raises is clear: what’s the problem with being keen? Isn’t it good to be keen? Before you entirely despair of my understanding of humanity, I do get it that some people don’t like to seem keen – and some people don’t like other people to seem keen. It’s both uncool and threatening. Cool and threatening is a gangster smoking a cigarette, pointing a revolver round the room. Uncool and threatening is a beaming intern with a photographic memory for business cards, projecting their diligence and youth round the office.

I learned this lesson myself when, as a student, I turned up at the Cambridge Footlights proclaiming my enthusiasm for getting involved. I knew that I wouldn’t get into a show just because I was keen, but I was surprised to learn that the keenness, or at least the expression of it, was an active barrier. I had to persuade some of the older undergraduates that wanting to take part wasn’t in itself a copper-bottomed guarantee that I’d be shit.

I have always found this sort of thing stupid and annoying. I hate boasting. I don’t think it polite for people to extol their own virtues. But it feels like nonsensical time-wasting to be forced to conceal your enthusiasms and ambitions. Whether it was invented by Scobie or the internet, the nickname “Katie Keen” is apt because she obviously is keen. She very much wanted to marry Prince William and has never seriously attempted to pretend that she could separate the human being from the exceptional circumstances he was born into. Who ever can with anyone? None of us is extricable as a person from all the things we’ve done and had done to us. She was uncomplicatedly up for the full package and, yes, that does include his penis.

But it’s interesting that Scobie, of all people, goes along with the notion that accusing someone of keenness is an effective slur. I understand why some royal commentators might do it: the royal family is supposed to project detached dignity, to rise above any betrayals of personal ambition. Dismissing the princess’s keenness as a sign that she was no more than a commoner who’s married into the family is an obvious way of deploying snobbery. But it seems odd coming from the Sussexes’ key advocate. Are they in favour of the royal family coming across as dry, unenthusiastic and entitled, projecting a world-weary noblesse oblige? God save the crown from those jumped-up enthusiastic outsiders?

It’s particularly strange because Scobie is himself so enormously keen. He has energetically carved out a large slice of the market for words slagging off the royal family. I recognise it because I’m in the same position. I’ve also written a book slagging off royalty and I’m also keen. Sadly, the royals I’ve chosen to slag off have been dead for more than 400 years so it’s more difficult to generate free publicity in the tabloids, though it lowers the publisher’s litigation risk. Still, I’ve been more transparent about naming royal racists: by 21st-century standards, the royals in my book were all racists.

My wife finds keenness a bit difficult to cope with. In fact, she suggested a joke about it which, I’m sure you’ll agree, is anything but cravenly mainstream: because of my keenness to mention my own book, she says I should call myself Dave Eager, and that would be funny because I would then have accidentally changed from a name that is identical to the acclaimed novelist David Mitchell to one that is similar to that of the acclaimed novelist Dave Eggers. I think that was the idea. I said it didn’t really work but she claimed that the four or five people on Earth who might understand it straight away would absolutely fall about. As someone who had to have it carefully explained, I can’t really comment on that.

Her own aversion to seeming keen is so ingrained that she hates buffets. The enthusiasm shown by merely walking up to a buffet table with an empty plate in the hope of loading up with lots of food and then having a nice large meal is, to her, an unbearable mixture of the gauche and the poignant. She approaches buffets stealthily as if about to be called out in mocking, sarcastic tones: “Oh help yourself! I expect you’re going to enjoy gulping down all that salmon!” The ambition even to have a big lunch is altogether too keen.

Intellectually, though, she agrees with me: society’s keenness aversion makes no sense. It gives sneering more power. It makes people shy about living their lives. Scobie claims the monarchy is a prejudiced, jealous, secretive, dysfunctional institution. If so, the disinfecting light of keenness is exactly what it needs.

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