Does editing a post ping ping-o-matic?

I’ve been noticing a lag when saving already published posts. On the same installation, I can “Save and Edit” or “Save” a draft prior to publishing and it’s nearly instantaneous, so the actual process of saving doesn’t seem to be the issue. Publishing is slow, but I know that’s to do with pinging. Does WordPress ping the ping servers when you edit an existing post? If so, can this be disabled? (I’m not pinging the links in the post, btw. I have that already disabled.)