This kind of thinking throws me into infinite loops. I think I'm not such a good developer, which makes me think that I must be a good developer because I recognize my limitations, which makes me think that I'm not such a good developer because I think I'm a good developer, and so on.
HN has a real problem with people who self identify as good programmers ... there is always a bunch of "no you're not" and "you only think you are" and "people who say they are good usually suck" type of responses. It's pretty weird reaction for a tech site where many good programmers hang out.
The problem is companies are looking for engineers while you are talking about this in terms of programmers. In most companies, it is about shipping and making a difference to the bottom line. It doesn't really matter if you are a good programmer if you are not getting things out of the door / ensuring future dev/maintenance will be pain free. For this programming is a tool, just like planning / estimation / design skills / being likable which helps with mentoring new developers etc. The % might differ, but the net evaluation has to be on the whole. Net results are also based on the big picture - what is your impact on the product? If we go by programming abilities alone, then managers must make base pay, which they don't. Also as you grow senior, the requirements change too.
And I don't know your scale of 'good' programmer either: What do you mean by that? Are you saying you are as good as Linus Torvalds or are you saying you are better than your current peers? I am assuming it is the latter - which probably means zilch in a site like this. Many folks here receive that recognition and over time they come to a conclusion that it doesn't mean much. Which is why you get a lot of naysayers. They aren't doubting you, they are just doubting the general feeling as been there, done that.
I don't think that is it. If you self identify as a good engineer/developer/progammer you get the same response. It's the self identifying thing that's seems to be the problem.
Look at this thread, there are several who are very explicitly doubting me in no uncertain terms. Even doubting the idea that I'm good compared to my current peers.