I’d try to look for the <?php the_excerpt(); ?>and <?php the_content(); ?> in the template-tags.php but no luck. Is there an option for the tagcloud widget to preview the tags “posts” in a different way? like little blogposts (without the whole tekst) or like an archive gallery? When clicking on a tag you get the total posts lining under each other but i like it more clear. You can view it here: foodsandphotos.nl on the right side the tagcloud widget.
You can’t randomly throw functions around like that because it might completely break your website. Make sure to do a full backup before you are attempting this kind of experiments.
template-tags.php has nothing to do with tagcloud and it serves a completely different purpose.
Tag cloud that you see in sidebar widget is generated by WordPress itself and theme only applies styling to it and there is not much that you can control with help from theme. To make any changes to this tag cloud you have to create completely new widget. As an example you can have a look at our custom widgets for this theme: Popular posts widget, social widget and category widget.