With regards to trying to understand how people react when you talk about home education, Leo asked in comments below: "Did you always believe in HE? Perhaps going back in time on your thinking could help you understand other people reaction's now".
That could be a very helpful question, though I think that my answer helps to explain my mystification with the sort of ambivalence one does experience. I personally vividly remember the first time I heard about Home Education, much as people remember where they first heard that about the WTC, or Reagan being shot. I had been worrying about submitting my child to the horrors of the British educational system since prior to his conception. He was 18 months old and I was desperately worried that I still hadn't solved this problem when a woman I barely knew (who subsequently, not altogether surprisingly became a good friend) told me that she had been reading about HE in the Natural Parent magazine. We were sitting rather shyly and a bit primly in her beautifully coiffured back garden but at that moment, I had to severely restrain myself from knocking the tea table out the way and hugging her effusively. The relief and the sense of the rightness of the idea were immense.
Perhaps this is why I find it hard to understand how people cannot immediately see that it could be the right way to go, (should one's child happen to choose it)...but perhaps the difficulty with realising the dream is what is informing the complex reactions one sees...I don't know.
Incidentally, Dh isn't a great deal of help in terms of trying to understand negative reactions. Whilst he was initially firmly of the opinion that Ds would go to school by the time he was seven, he immediately saw that HE was right for the first few years. Ds is now past Dh's required school entry age, so it was with some interest that HE friend and I eaves-dropped upon his recent conversation with someone unacquainted with HE. He sounded like a true believer, a proper advocate, with a full understanding of the idea of autonomous education and all this for children of all ages. Friend grinned about this from ear to ear!
I would love to hear more about your doubts, Leo. Am I right in thinking that you are concerned about foreclosing on your child's choices by not being able to offer him a full range of knowledge? Or is it more a matter of difficulty with managing the logistics?
For more stories on how people first heard about HE, there's this page at the Education Otherwise site.