I read in a book about an experiment during which people were given a square of their favorite chocolate and had to rate whether they wanted more after the last piece or if they didn't want any more. The more chocolate they had after a certain point, the less they wanted.
They were either eating the wrong chocolate (probably! milk chocolate is sugar) or were not real chocolate fans.
When I am eating my favorite dark chocolates (90% Lindt or 87% Laima, a Latvian chocolate), I have to hold myself back from eating ever more of it. Both of these chocolates are low in sugar, sugar being further on the list of ingredients compared to other chocolates. So it's more chocolate than anything else, though it isn't bitter like some of those chalky high-percentage chocolates that really don't understand the potential of chocolate at all.
So I guess if I were in that experiment, I would skew the results, and happily.
I say as I eat some dark chocolate accompanied by a mug of chocolate-and-orange rooibos.