Simple CommentSpam hack?

In the WordPress Admin GUI: Options/Discussions are two Comment Moderation filters: Number of URLs allowed in a comment and a list of forbidden words.
In the functions.php file is the function check_comment which matches against ‘comment_max_links’ and the forbidden words, called ‘moderation_keys’. (Ought to be called ‘forbidden_words’)

If I after the line: $word = trim($word); add the line $word=strtolower($word); I don’t have to worry about upper and lower casing the forbidden words.

Then: If check_comment returns false we set the variable $aproved=1.
If I under this line add the new line: die( __(‘Spam word encountered. Comment not allowed’) );

Would I not make the default WordPress spamguard stronger and allow it to simply discard all comments flagged before they reach the moderation queues in the comment table?