D-link

There are three means of creating unobtrusive, or at least visually
appealing d-links:

1. Use the CSS DISPLAY property to prevent the d-link from being presented
in a graphical rendering of the page. For example: <a
href="description.html" style="display: none"> D </a> Note that the link
would nevertheless be displayed by speaking browsers, or exposed to
assistive technology via DOM or similar mechanisms. One might also use a
CLASS value and specify the style in the HEAD section of the document.

2. Use an invisible image with ALT text as the content of the d-link: <a
href="description.html"> <img href="invisible.jpg" alt="D"> </a>

3. Use a stylised d-link graphic. The code would be the same as that
exemplified in paragraph (2) above, save for the content of the image
file.

I think the page author guidelines need to recommend one or more of these
strategies, perhaps in an appendix, and include at least a single example. 
This issue was raised in the authoring tool discussion held as part of the
WAI meeting at the WWW7 conference.