Yes bodybuilders do that but the article isnt really talking about water manipulation in the way that they would go about it.
Fitness models and bodybuilders do crazy stuff to get ready for contests or shoots in those final days to look as good as possible. And that includes drinking to further dehydrate. I have heard if you arent buzzed you probably arent ready.
The article was more about why sometimes even on a calorie deficit you dont see consistent weight loss and how it sometimes seems to fall off in chunks.