One of their big problems is confusing the word generation with lifespan.
1914 to 1994 would be an 80 year lifespan. People started to get antsy.
But the word generation was always used to describe a group of contemporaries in modern parlance. Hence: the Greatest Generation, the Baby Boom Generation, Generation X, etc.
Suddenly, WT decided to use that, in a sense, updated, definition of the word. A group of contemporaries overlapping in age. Yes, you could be born anytime between 1946 and 1964 and still be part of the Baby Boom Generation, even though individuals could have as much as 18 years in age between them.
But, they bastardized this to mean some gobbledygook wherein a grandfather is an overlapping generation with a grandson and the lengths of their separate lifespans added up to something they called an "overlapping generation." This is a completely made up idea. It's a made up word with a made up usage. Of course it's incomprehensible: it's an idea that doesn't actually exist in reality.
Demerits for misuse of the English language.
I award no points and may God have mercy on your soul.