At first glance, the note in "Barry" Obama's 1979 high-school yearbook seems innocent enough. "Thanks Tut, Gramps, Choom Gang, and Ray for all the good times," it reads, under a black and white photograph of Obama, then just 18, playing basketball with a friend.
To those familiar with the early life of the 44th US president, "Tut and Gramps" are an obvious reference to Obama's maternal grandparents. He'd gone to live with them at the age of 10 because his mother had taken a job in Indonesia and his father had disappeared when he was still a toddler.
But what of the "Choom Gang" and "Ray"? Not even in Dreams from My Father, Obama's detailed and unflinching memoir, is any explanation given.
When the yearbook first surfaced during the 2008 presidential campaign, it was thought that the Choom Gang was simply a mischievous term for Obama's fellow pot-smoking basketball players at Honolulu's Punahou prep school (to "choom" meant to drag on a spliff in late-1970s Hawaiian vernacular).
As for Ray, journalists concluded this must have been Obama's childhood friend of the same name, described in Dreams from My Father as two years older than the future president, but a close friend due to the blackness of his skin.
But those charmingly naive assumptions may have turned out to be misconceived.
This 656-page biography of Obama by David Maraniss, the Pulitzer Prize-winning author, has made extraordinary claims regarding the back story to that high-school yearbook entry.
Needless to say, it probably wouldn't have gone down very well in 2008, when Obama was still a largely untested first-term senator from Illinois.
The book alleges, for example, the Choom Gang was not just a cheeky name for a few basketball players who'd once tried a joint. No, the members of this group - not all of them sportsmen - dedicated most of their spare time to getting baked in a variety of ever more imaginative ways, often while crammed in the back of their "Choomwagon" - an old VW bus.
And Ray? Not the same Ray from Dreams from My Father. Oh, no. Maraniss alleges that he was "a long-haired hippy who worked at the Mama Mia pizza parlour, not far from Punahou, and lived in a dilapidated bus in an abandoned warehouse".
More to the point, Ray was a "freakin' scary" dope dealer, supplying the young Obama with such exquisite mind-altering herbs as Maui Wowie, Kauai Electric and Kona Gold.
Which brings us to the great irony of the Choom Gang allegations. In the years since Dreams from My Father was first published, America's attitude towards marijuana has changed beyond any recognition.
In many parts of the US, the drug is openly available without fear of prosecution.
In that context, Obama's apparently highly selective and overwrought confessions from 17 years ago now seem a lot less daringly honest than they were at the time.