In WordPress, by default, when you click on the Read More link, the web page loads and then “jumps” to the spot where the <!--more--> tag is set in the post. Whether you like this effect or not is personal preference, but it can pose an SEO problem.

The Problem

The problem is that it creates two different links to the same page. For example, here would be the two links to Paul’s last article:
http://www.search-this.com/2007/11/26/css-a-recipe-for-success/
http://www.search-this.com/2007/11/26/css-a-recipe-for-success/#more-464

So what can sometimes happen is that if the article becomes popular, half the people will link to it one way while half the people link to it the other way. Thereby dividing the total link juice in half.

The Fix

The only way I have found to fix this is to modify a file in the wp-includes directory.

For WordPress 2.2 and up modify the post-template.php page.
For WordPress 2.1 and below modify the templates-functions-post.php page.

Somewhere around line 124 comment out the $output line with the "#more-$id\" in it and change it to the below:

Just remember that each time you upgrade WordPress you will need to remod this line. But if it helps out with SEO it’s a small price to pay.