I bring my own experience: I weighed myself before and after a long and very hot bath and my weight after the bath was about 0.8 kg less than the starting weight.
The body, sometimes, reacts completely counterintuitive: I prefer to rely on my own experiments data and results,
I have never heard a convincing argument about how a hard dry fast is better than a soft dry fast. Even if I completely avoided showers it would be impossible for me to have no contact with water just based on the area I live in. I also dont live alone so I dont want to be a complete gross ass.
Our skin absorbs water which means that later in a dry fast, you will absorb water more readily, especially when your body is in a dehydrated state. Also, some bacteria thrive in water, so brushing your teeth allows them to continue to live. If you don’t brush your teeth for a long dry fast, it helps eradicate bacteria and infections in the mouth