From an article someone posted downthread ( https://news.ycombinator.com/item?id=49246228 ) :

> Mars could appeal to a more exciting chocolate eater, and a smaller lighter bar could increase consumption per capita: “While people loved the anticipation of biting into the chocolate, they often found that the bar lay rather heavily on their stomach at the end of eating it.

> “Which means they wouldn’t eat another, sometimes for the rest of the day.”

So the big change was a cynical attempt to make people eat more, not less.

The part that has dated most about that quote is that in 2002, Mars were happy to put that on record!