I had an acquaintance who tried this with her children. She was a very "natural" kind of person. No antibiotics, vaccinations or other sorts of official medicines for her children. She breastfed them until they were four or five and usually had two or three nursing at a time. She believed her children would learn good behavior from natural consequences of their actions. Consequently they were ill-behaved brats with green snot hanging out of their noses most of the time.
BUT .... they were potty trained by the time they could walk. At least she was. The only problem happened when she got distracted by a younger baby and the little one had an accident in his "big boy" pants. Yuck.
I think the method can work for very dedicated mothers. However, I came to believe that it had made this woman's children very unnaturally focused on their eliminations. They talked all the time about body functions, had their hands in their pants all the time. Thought everybody else wanted to talk about, see and otherwise participate in their eliminations.
Personally I think that parents put a huge amount of dedication and decision making into the whole potty training thing. But in the end, it's the child who decides whether to respond or not.
My oldest son realized his poopy diapers smelled bad at the age of 2 years and one month. When I told him that he could use the potty just like Mommy and Daddy and then his poop would just flush away and not smell bad, he was immediately sold. End of story, no moe wet or dirty diapers.
Youngest son had so many ups and downs, poor kid had a rough time. He would just get it down and then would get sick with something and it would set us back. So finally I told him that when he turned 3, the rules said moms couldn't change diapers any more. I put all the supplies down on a bottom shelf and told him that the day after his third birthday he would have to start cleaning up his own diapers. About a week before his birthday he came and asked me if I really meant it, that he would have to be in charge of his own diapers. I assured him I was (and by this time I was ready to live with the consequences of my decision). He looked at me a long minute and then said "Ok, I guess then that I need to use the potty."
End of story. No more diapers. There were a few wet pants when he started kindergarten a couple years later, but that faded when he was reassured and comfortable with school.
I know all about pollution and land fills and carbon and global warming. But the answer to all this can't be constant focus on your baby's elimination needs. There's got to be a better way than saddling moms with yet one more guilt-ridden task. Somebody else can save the world for a change.
Sunny