Comment form won't appear in my theme I can't get the comment form to appear in my theme.  It does appear in Garland, but not in Bartik.

I have copied node.tpl.php and comment.tpl.php into my theme from Garland. 

I have added text to the node.tpl.php template to ensure that it is in fact the relevant template for the node.

I checked the page source to see if perhaps the comment form is appearing, but is hidden by CSS.

I deleted ALL code from the template.php file in the theme.

I have cleared the cache and run cron after doing all of the above.  

I've built more than 100 Drupal sites, so I'm not exactly new to the framework.  And yet I can't get the comment form to appear in this theme.

Clearly I must be doing something wrong, but I can't think of what else to check.

Any ideas?  

Remember, the comment box does appear in Garland, so this can't be a permissions issue and can't be due to settings in the node itself.

The Drupal version is 7.41.

Thank you.
The "Comments block" module was the cause of this.  The module appears to be functioning as intended.  I just hadn't encountered this contributed module before, and didn't realize the project made use of it.

Because the "Comments block" module is installed, the "Comment form" block must be added to a region (e.g. "Content") in the theme.  This explains why the comment form was appearing in some themes but not in others.