Join Date: Jun 2017
Location: Staffordshire - United Kingdom
It's indeed very possible, my late father did just this, with some adaptions. Also, like others have stated, it is actually incredibly close to the Diana Walstad method, well, the method she made famous, but certainly didn't invent as such. Modern day equipment certainly helps depending on what you are wishing to achieve, size of tank, type of creatures in the tank and more. I would say he's an older gentleman who is doing something that works for him, with a little too much confidence in advising as a blanket statement, it'll be perfect for every situation and everyone.
Whilst there are many wrong or immoral things to do in this hobby, much of the products, techniques and so forth are all just personal experiences. Personal to your water supply, where your fish were imported from, how they were then treated by the LFS, the breeding lines, the light of the tank, the quality of light, the temperature in the tank, the quality of the plants, the differences in this and that and this and that. You get the idea.
Simply put, if everyone around the world followed the exact same "rules" as such, it would not be the case you'd see the same results. So I always recommend anyone joining this hobby, or anyone in this hobby for a while, to take all the advice they can, and do what works for them personally. So take aspects of common sense, plant knowledge, biology and so forth. Combine all of this and do what works for you.
Simply put, he's not completely wrong, but not right at all for many depending on what your equipment, circumstances and so forth are.