I've been trying to modify a multiple-values field in a view. I thought I'd found the answer, creating a custom .tpl.php file using the naming structures detailed in Views UI's "Theme information" popup.

However, it seems that these tpl.php files are only respected when the field is output immediately, and not when it's set to be excluded from the display and then rewritten into another field using a replacement pattern. Views is seeing the file, and uses it if I don't have "exclude" ticked, but if I use a re-write pattern for the field, Views completely ignores the tpl.php file.

This happens regardless of whether "Use field template" is ticked for this field in Views UI's field Style Settings.

I almost always aggregate my fields like this to control the HTML output. How can I make Views respect my tpl.php file when re-writing the field content into another field?