<p><pre><code> • Uncertainty on the part of the speaker about the accuracy or credibility of the
content
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I think it makes sense (hah!) to periodically ask your audience if they're still with you, especially if they have confused looks on their faces. It's an invitation for feedback. Also, depending on the subject at hand, it might not be a bad idea to show some humility and allow people to express doubts about the accuracy of the content.<p><pre><code> • Doubt about the ability of the audience to comprehend or appreciate the content.
</code></pre>
I don't think so, but that might be because I'm not a native speaker and this implication could well be one of those finer points that are lost on me. "Does that make sense?" is not the same as "Did you manage to understand this?" In my native language, speakers use the latter more often (typically using an inflection suggestive of the fact that the audience is entirely composed of brainless maggots who crawl before a glorious superior being) and I do find it insulting, but I believe these expressions are very different from each other.