It's against HN's rules to ask friends to upvote and (especially) to post comments in threads. We want people to upvote and comment because they ran across something that they personally found intellectually interesting, not because a friend has something to promote. Promotional use of HN voting and commenting is opposed to the spirit of the site, and the community is adamantly against it, as you can see from the comments making objections to the earlier pattern in the thread.
Thank you for drawing this line clearly. Frequently elsewhere I see mods decrying self-promotion, yet there should be nothing wrong with posting your own material (otherwise, what is the internet for, only consumption?). The problem comes when you beg people from outside the community to give you recognition through forced comments/votes.