first it isnt usually considered a good idea to have the same article in its entirety in multiple places on your site. you can get a duplicate content penalty from google.. they'll basically look at your site as spam.
but if you want, you can do the exact same thing w/ more conditional logic.
the whole thematic_content function (in the extensions folder under content extensions) looks like:
//creates the content
function thematic_content() {
if (is_home() || is_front_page()) {
$content = 'full';
} elseif (is_single()) {
$content = 'full';
} elseif (is_tag()) {
$content = 'excerpt';
} elseif (is_search()) {
$content = 'excerpt';
} elseif (is_category()) {
$content = 'excerpt';
} elseif (is_author()) {
$content = 'excerpt';
} elseif (is_archive()) {
$content = 'excerpt';
}
you can see that it is set to excerpt for the types of pages you'd like to change back to full. so you would expand your child function by adding conditions for archives and tags
function childtheme_content($content) {
if (is_category()) {
$content= 'full';}
elseif (is_tag(){
$content= 'full';}
elseif (is_archive() {
$content= 'full';}
return $content;
}
add_filter('thematic_content', 'childtheme_content');
for more on WP conditional logic: http://codex.wordpress.org/Conditional_Tags