Seldom has one word proved so controversial. By lunchtime that day I had been well and truly lobbied over what to write. And what not to write.
Had I reunited Ben Langdon and Mark Wnek over a cosy lunch at the Wolseley, or offered David Herro shares in a newly floated M&C Saatchi, I doubt if the response would have been as heated.
"If you write one favourable word about Lovemarks I will cancel my subscription to Campaign," one reader wrote. A pro-Lovemarks person sent me a long dissertation on why advertising needs more of Roberts' business advice.
It is, of course, extraordinary that one silly little book can cause such strong feelings. But then Lovemarks, for Roberts and his fans, is not just a silly little book. It's a world. It's a way of life. It's a way of dressing (black, always). It's a way of sucking up to your biggest clients in public ("I love Head & Shoulders. I won't buy or use anything else. It's a Lovemark of mine"). It's a way of getting ahead.
How to encapsulate the message of this 228-page book for readers who may not be tempted to rush out and get themselves a copy?
Basically, Lovemarks are based on weaving Mystery, Sensuality and Intimacy into every brand. But what does this mean in practice? I will open the book at random on a few pages and tell you what I find there. Here goes ...
Page 119. Shows the front cover of the January 2004 issue of Architectural Digest, which carries a feature about Roberts' beautiful and aggressively minimal New York apartment. It has a Portuguese limestone floor, we learn, that is quiet and tactile and "caresses my soles".
Page 56. We learn about the evolution of Lovemarks. As Roberts watched various Saatchi showreels of TV commercials during his first few months on the job in 1997, we learn that he became convinced that only an emotion like love could power the next evolution of branding. We learn, to our relief, that grown CEOs blushed and slid down behind their annual accounts when Roberts suggested that Love was the way to transform their business.
Page 186. Tells the fascinating story of how Saatchis put the Lovemark ideas into practice (or perhaps post-rationalised its thinking) on to a successful case study for Olay, taking a bog-standard moisturiser brand into the prestige skin-care market for the first time.
Almost every page is full of a combination of unintentionally humorous observations. A heady mixture of sense and nonsense, banality and pretension.
All of this is couched in the kind of emotional patois written exclusively by chief executives who have worked in the US for much of their career.
Brits, of course, find this kind of business advice particularly hard to take. We like more hard facts and less straight-from-the-heart stuff. Our only response is cynicism. Roberts can preach all he likes about the role of love in business and branding, but I just can't get away from the sneaking suspicion that successful advertising CEOs are among the least loving and least soft-hearted members of the human race. Still, try it for yourself at www.lovemarks.com. And in next week's Campaign, there's Francesca Newland's interview with the man himself to look forward to.