Is there any drawback to using the description field to hold say 4 sentences of text?

<?php if($content['type']=="reference" || $_REQUEST['a']==72) { ?>
One thing to try would be to just change that if statement to if(false). Then weblinks should be treated as regular documents and you’d get all the fields. A trickier fix would be to edit that first section to add the summary/introtext field based on what’s in the "else" section.
// Web Link specific
?> <tr style="height: 24px;"><td valign="top" width="100" align="left"><span class="warning"><?php echo $_lang['document_summary']?></span></td>
<td valign="top"><textarea name="introtext" class="inputBox" rows="3" style="width:300px;" onchange="documentDirty=true;"><?php echo htmlspecialchars(stripslashes($content['introtext']))?></textarea>
<img src="media/style/<?php echo $manager_theme?>images/icons/b02_trans.gif" onmouseover="this.src='media/style/<?php echo $manager_theme?>images/icons/b02.gif';" onmouseout="this.src='media/style/<?php echo $manager_theme?>images/icons/b02_trans.gif';" alt="<?php echo $_lang['document_summary_help']?>" onclick="alert(this.alt);" style="cursor:help;" spellcheck="true"/></td></tr>
<tr style="height: 24px;"><td><span class="warning"><?php echo $_lang['weblink']?></span> <img name="llock" src="media/style/<?php echo $manager_theme?>images/tree/folder.gif" width="18" height="18" onclick="enableLinkSelection(!allowLinkSelection);" style="cursor:pointer;" /></td>
<td><input name="ta" type="text" maxlength="255" value="<?php echo !empty($content['content']) ? stripslashes($content['content']) : "http://"?>" class="inputBox" style="width:300px;" onchange="documentDirty=true;" />
<img src="media/style/<?php echo $manager_theme?>images/icons/b02_trans.gif" onmouseover="this.src='media/style/<?php echo $manager_theme?>images/icons/b02.gif';" onmouseout="this.src='media/style/<?php echo $manager_theme?>images/icons/b02_trans.gif';" alt="<?php echo $_lang['document_weblink_help']?>" onclick="alert(this.alt);" style="cursor:help;" /></td></tr>
<?php } else {
// Document specific