Prune without users losing post counts

[telc]

When pruning threads I would like to preserve users post counts.

In includes/functions_databuild.php

Within "function delete_thread("

If I remove this query will it stop users post counts from getting decremented when I prune threads. Can you see this causing any other issues.

PHP Code:

$DB_site->query("
    UPDATE " . TABLE_PREFIX . "user
    SET posts = posts -
        CASE
            $casesql
            ELSE 0
        END
    WHERE userid IN (0$alluserids)
");