<p> Well yesterday I talked about <code class="verbatim">C-o (open-line)</code> that opens up additional lines beneath the line you&#39;re currently on, and how little I used it.</p> <p> A related key that I use even less, but could see more opportunity for, is <code class="verbatim">C-x C-o (delete-blank-lines)</code>, which collapses repeated lines of whitespace into a single line.</p> <p> The first thing I find myself wondering, though, is &#34;Why <code class="verbatim">C-x</code>?&#34; It seems to me that most other commands like this—variations on a shorter set of keystrokes—use the <code class="verbatim">C-u</code> prefix to say, &#34;do the opposite-ish&#34;.</p>