I was told that such behaviour is useful for someone else as if they come across either post the ping links them so providing a fuller picture of what you have posted.
I understand that the WordPress default is to ping all URLs in the post indiscriminately but I question whether a pingback from your weblog to your weblog is a very useful thing. I mean, isn't it fairly common to put things in your posts like, "the other day when I wrote about this", and have a link back to that post? In that case you've already explicitly made the link so that users can come across the post. Is it really that useful to have a pingback? Is it in keeping with the spirit of the whole pingback idea?
If you look at the Codex entry for pingback it says, "Pingback lets you notify the author of an article if you link to his article (article on a blog, of course)." I think that the spirit of the whole Pingback idea is to notify other authors that you're linking to them, not to "notify" yourself. Same thing if you look at the official pingback specification: "Pingback is a method for web authors to request notification when somebody links to one of their documents."; notification that "somebody" has linked to my document, not a reminder that I have linked to my own document.
This could actually be very useful if it were neatly formatted in the form of a "related links" section, but the trouble is that the pingbacks are mixed in with the comments and tend to be fairly ugly. Stuff like this:
[...] [...] Chapter 04 [...] [...]
Do you really want ugly pingbacks like that appearing in the comments?
It seems a shame that in order to suppress these unnecessary pingbacks you have to turn off the functionality entirely, or manually delete the unwanted pingbacks every single time you make a post, or avoid the pingbacks by forgetting about providing your users with useful references to related documents. I am totally new to WordPress but I am going to take a look at the code and see how much would be involved in suppressing this undesirable behaviour.