Its more that for claims you are making, people want to see something more concrete than someones word, especially in a topic that has a bunch of snake oil going around.

In my brief searching it looks like one might be able to train up to doing longer periods of going without water, but there seems to be a lack of study on the matter (probably hard to get a study past a review board due to the danger you are placing people in).

What is the mechanism by which fasting for 10 days helps "any sort of disease modern medicine is telling you is incurable" (as you say in another comment that is no dead so I can't reply)?

Are there any studies into the health benefits of not drinking water for 30 days?