That's ok if the manage_boardrules template is larger. I don't see any duplication, add and edit can all be handled by just using S_ADD, S_EDIT and S_PREVIEW swicthes:
All the add and edit code can be done with just this:
```
<fieldset>
	<legend>{L_RULE_SETTINGS}</legend>
	<dl>
		<dt><label for="rule_title">{L_RULE_TITLE}{L_COLON}</label></dt>
		<dd><input class="text medium" type="text" id="rule_title" name="rule_title" value="{RULE_TITLE}" maxlength="255" /></dd>
	</dl>
	<dl>
		<dt><label for="rule_anchor">{L_RULE_ANCHOR}{L_COLON}</label></dt>
		<dd><input class="text medium" type="text" id="rule_anchor" name="rule_anchor" value="{RULE_ANCHOR}" maxlength="255" /></dd>
	</dl>
	<dl>
		<dt><label for="rule_message">{L_RULE_MESSAGE}{L_COLON}</label><br /><span>{L_RULE_MESSAGE_EXPLAIN}</span></dt>
		<dd><textarea id="rule_message" name="rule_message" rows="6" cols="70" data-bbcode="true">{RULE_MESSAGE}</textarea></dd>
		<dd><label><input type="checkbox" class="radio" value="1" name="enable_bbcode"<!-- IF S_MESSAGE_BBCODE_ENABLED or S_ADD --> checked="checked"<!-- ENDIF --> /> {L_PARSE_BBCODE}</label>
			<label><input type="checkbox" class="radio" value="1" name="enable_smilies"<!-- IF S_MESSAGE_SMILIES_ENABLED or S_ADD --> checked="checked"<!-- ENDIF --> /> {L_PARSE_SMILIES}</label>
			<label><input type="checkbox" class="radio" value="1" name="enable_magic_url"<!-- IF S_MESSAGE_MAGIC_URL_ENABLED or S_ADD --> checked="checked"<!-- ENDIF --> /> {L_PARSE_URLS}</label>
		</dd>
	</dl>
	
</fieldset>

<fieldset class="submit-buttons">
	<input class="button1" type="submit" id="submit" name="submit" value="{L_SUBMIT}" />&nbsp;
	<input class="button1" type="submit" id="preview" name="preview" value="{L_PREVIEW}" />&nbsp;
	<input class="button2" type="reset" id="reset" name="reset" value="{L_RESET}" />
	{S_FORM_TOKEN}
</fieldset>
```