Where by "self promotion" you mean "sharing his thoughts"?
>Please don't use HN primarily for promotion. It's ok to post your own stuff part of the time, but the primary use of the site should be for curiosity.
His submissions here are usually to his own work. Admittedly, that HN guideline is like an obscure 19th-century law which is still on the books that few know of and is never enforced. Even so, he's clearly well-regarded based on the amount of conversation his blog posts elicit.
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