I’m experiencing exactly the same problem as kvcrawford.
The WYSIWYG editor wraps the <img> tag in [caption] tags, like this:
[caption id="attachment_141" align="aligncenter" width="400" caption="caption text"]<img class="size-full wp-image-141" title="pic title" src="https://www.summitcove.com/wp-content/uploads/2009/08/img1.jpg" alt="alt text" width="400" height="300" />[/caption]
But the <img> tag doesn’t appear in the markup on the front-end until I remove the [caption] delimiters.
I added the css needed for the WordPress Generated Classes to my style.css file. No luck. It seems to me like you’re suggesting that the markup doesn’t appear unless the necessary css is detected by WordPress?
If that’s not the case then at the very least the HTML should be there, right? I’m kind of a WP noob.