@rollitup
You're certainly entitled to your opinion. With all due respect, I think you're missing the point. The method shows that hydroponics can be viable in the absence of power for things like air pumps and water chillers. If you're at all curious, there are a ton of videos on YouTube. Kratky has proven itself to be commercially viable for producing all sorts of greens.
Is it the best way to grow cannabis? Certainly not! But the implications for poor areas without access to electricity to be able to grow their own food, and quickly (lettuce takes ~30 days), to me is anything but ridiculous.
I like to learn new things, try unconventional approaches to conventional activities, such as gardening. That's all this is for me, a fun side project.