So having mulled it all over for a few days, I've come to the conclusion that there is an insane amount of pressure on parents to get their child reading successfully. And my previous post didn't help at all with that! Sorry. I now feel terribly sympathetic towards parents of children who are behind their peers in reading, because I suspect it's easy to feel guilty or blamed.
Lana's comment about needing her daughter to be at least as good as her rung true with me. I feel that if I was reading at three, then my son should be as well, and that's a silly way to look at it. Since my original post, I have dutifully researched late reading. Here are a couple of interesting pages:
Why the Waldorf Method Waits
The Unschooler's Account of How Children Learn to Read
With regard to the second link, any readers should bear in mind that the writer was relying on people emailing him with their accounts, and people are always happier to contribute their success stories than their failures. Also, from the little I know of unschooling, it's bucking against the traditional school model and formal education rather than avoiding education altogether. I suspect many parents of unschooled children are, intentionally or not, employing elements of other self-directed learning methods.
Regardless, late reading isn't for me. We'll see if either of my children change my mind on that score.
My actual conclusion is that motivation is probably the most important factor. My son loves books, so I should stop worrying about him and start worrying about my eleven month old daughter... I kid. Actually, she's already beginning her pre-reading skills, since every time I pull out a book, she hauls it off me and practises opening and closing it. I usually have to let her do this for a few minutes before we can get on to the story part....
Because I wanted to be reading independently at the age of three, sight-reading was absolutely the right choice for me. My son is perfectly happy for me to read books to him; his current fascination is with letters (or 'sounds' as we call them), so I'm trying to come up with various alphabet activities to capitalise on that. I'm not actively testing him, but he's got most of the lower case alphabet down now and a good portion of the upper case (b, p, d and q are of course all over the place).
We discovered over Christmas that he can sight-read his name, because he loved finding it in every Christmas card we received. Sitting down with the flashcards isn't really my style, so I'm not going to push that. If he starts asking me to point out words for him, that might be different, but we'll see what happens.
Mostly, what I'm going to do is keep track of his skills. It seems that the problem with any method of reading is that literacy is about more than just reading. You can't just get your child reading The Very Hungry Caterpillar and say: "Job's a good'un!" Spelling, grammar, comprehension and articulation require a lot more than recognising words on a page. A sustained effort from both child and educator is required on the various language skills, and that's why you need a lot of enthusiasm to start with.
To that end, even if he teaches himself to sight-read, I'm going to continue doing phonic activities with him, encouraging him to listen to the sounds of words. I suspect that, like myself, my son is a visual learner, but I'd rather he didn't end up with my dearth of listening skills!