Yes, it works very well. Unschooling (as the Americans call it) aka "autonomous education" (as it is more commonly known here) has served my two well. They are now aged 20 and 13. We know a number of other families who do the same.
It isn't as risky as you think.
Imagine that you had always feared your children wouldn't eat if you didn't push food on them, and had always tried to insist that they eat at mealtimes as well as urging snacks on them at frequent intervals. So they never had the opportunity to get properly hungry, and perhaps they regularly pushed food away. Being tired of having food pushed on them all the time, they might never actively seek food out. They might even say they hated food. This might make you even more anxious, convinced that left to their own devices they would starve.
Perhaps a more chilled friend would try to persuade you to allow your children to decide for themselves when they were hungry. You might tentatively try it, refraining from pushing food upon them for as long as two or three hours. But if your children showed no interest in food within that time you would conclude that the experiment was a failure and you must make them eat.
Learning is like food. Children have a natural hunger for it. That's easy to observe in very small children as they explore and ask a million questions. When children get a bit older, nearly all parents begin requiring kids to learn what we want them to learn when and how we want them to do it. They may well get fed up and say they hate it. But once we stop badgering them, their enthusiasm returns. Unfortunately the school holidays aren't usually long enough to see this happen, so most parents don't believe that it will happen.