<p>I agree with @amoeba: it's important that authors have the ability to update or improve their question as quickly as possible. Otherwise it may be closed as unclear, or answers that do get posted will fail to address the author's main concern. We have many ugly, hard-to-follow threads that are a nightmare for future readers, resulting from substantial updates or clarifications appearing after some answers have already been given. It is certainly worth trying to prevent this.</p>

<p>I frequently approve such edits. But I also post a note saying:</p>

<blockquote>
  <p>Please register &amp; merge your accounts (you can find information on how to do this in the <strong>My Account</strong> section of our <a href="https://stats.stackexchange.com/help">help center</a>). Then you will be able to edit &amp; comment on your own question.</p>
</blockquote>

<p>Copy-and-pastable text:</p>

<pre><code>    Please register &amp;/or merge your accounts (you can find information on how to do 
    this in the **My Account** section of our [help]). Then you will be able to 
    edit &amp; comment on your own question.
</code></pre>

<p>Clues that this is what is going on:</p>

<ul>
<li>The question is recent,</li>
<li>Both the original account and the editing account are new (or the edit is anonymous, which indicates the author has logged out - I would post a slightly different comment in that case, suggesting that the author should log in),</li>
<li>The edit contains a clarification, or adds some information that only the original author would be expected to have.</li>
</ul>

<p>It strikes me as remarkably unlikely that a new question with fewer than a dozen views not only will be stumbled on by a random visitor, but also that they should have mistakenly attempted to edit and improve it.</p>

<p>If I ever get a confused comment from a surprised poster wondering why somebody else has edited their question and reslanted it with their own additional information, then I will know I've made a wrong call, but it hasn't happened to me yet!</p>
