It's baffling, because I can look at the file with Fetch/BBEdit (a Mac FTP program & editor, for you Windows people) or even log into the site's cpanel and use that file manager to look at the file, at the code is correct. If I delete the file (header.tpl in this case), the postlist page displays as expected without the header (no CSS and no header links, etc). But no matter what I do in terms of uploading, the file does get uploaded and does contain the new code, but displays in my browser as the old code/page.

To be thorough,
  • I've cleared my browser cache
  • Looked at it in different browsers
  • Looked at the file on the server via different FTP programs (Dreamweaver, Fetch, CPanel's File Manager)
  • Tried uploading a test.html file (which worked)

Arrgh! Thanks for the help, I'm appreciating it!