Don’t bother trying to change the title of a post. You can’t do it using ordinary commands. Once you give a post a title and publish it, WordPress will not let you change it.
It’s not obvious, nor is it explained anywhere obvious. I found it hidden away in a support forum http://wordpress.org/support/topic/change-post-html-title which said, “Also you can change the name of the title, I have. Just need to remove the annoying >> thing.” Well, changing that “>> thing” isn’t particularly obvious and doesn’t appear to be supported by regular commands. I could spend hours looking for it. But I’m not going to.
To change a title, I start a new post with the title that I really want, paste in the text from my old post, delete the old post, and get on with life.
Okay, I was wrong, except the part about “using ordinary commands.” To change the title, you can edit the Permalink right below the title box. And that may goof up the ability of other pages to link back to the original Permalink
Post post script: Yes, changing the permalink title definitely will mess up links to your article! Other web sites and Google crawlers have found your article previously and are looking for the old title. When it’s not there, they get what is called a 404 error message. I had a nice link from another blog. I messed it up by changing the permalink. Fortunately, I noticed, and went back and changed the permalink title, and it started working again.