Sorry I wasn't clear or maybe I'm not understanding something (or maybe this is a theme function) but . . .
Until 1.5.0, if I checked the "Allow title from alt tag" option, when img tags were generated, whatever we had in the Alt Text field in the WP media editor/uploader would be substituted for what was in the Title field -- whether or not the Title field was empty. And if there was no text in the Alt Text field, even with the option turned on, the alt attribute value was set to what's in the Title field. (So we spent a lot of time editing over the last four years copying and pasting stuff from the Caption field to the Alt Text field.)
In the new version, this behavior (basically, use Alt Text if it exists) still happens with single or multiple images embedded in a post. (Meaning even if there's text in the Title field, the img tag is generated with an alt attribute that clearly came from Alt Text field.) But it doesn't happen with img tags generated by the gallery shortcode -- with those, now I have to delete all the text in the Title field for it to use the Alt Text.
So I'm just wondering if I have to delete the contents of the Title field in the WP image editor for like 300 images or not. If so, it's fine, your plug-in is worth it -- it just seemed like something had changed.