Empty content creates an extra <BR/>

You can try

.entry-content ul{ margin-top: 0;}

in your stylesheet.

The empty content is usually when you have a sitemap or archives template which is usually listing items. So the content div after the post/page title is followed by a ul. So remove all the extra space you can when that situation arises and it mitigates the effect of the <br />.

You could even be more specific and try to isolate only those pages using the page id.
body.pageid-xx .entry-content ul{ margin-top: 0;}

Note I am using SandboxPlus theme so have taken my css selectors from there. You would have to look at what your theme does.

I have narrowed down where this is happening. It is a part of the filtering process by the function “wpautop” in the file: {wp-location}\wp-includes\formatting.php
This is the comment describing the function:

/**
 * Replaces double line-breaks with paragraph elements.
 *
 * A group of regex replaces used to identify text formatted with newlines and
 * replace double line-breaks with HTML paragraph tags. The remaining
 * line-breaks after conversion become <<br />> tags, unless $br is set to '0'
 * or 'false'.
 *
 * @since 0.71
 *
 * @param string $pee The text which has to be formatted.
 * @param int|bool $br Optional. If set, this will convert all remaining line-breaks after paragraphing. Default true.
 * @return string Text which has been converted into correct paragraph tags.
 */

You can disable the $br argument, but then all
tags will be removed. I don’t believe wordpress generates br and p tags by whitespace. A workaround is to check to see if the content is empty, then do some conditional processing:

if(get_the_content() != ""){
	the_content('Read the rest...');
}

thewebdude – THANK YOU! the conditional worked perfectly in a template i am working on. much appreciated.