Yes, Troy McClure have read WCAG ;-)

http://www.w3.org/TR/2010/NOTE-WCAG20-TECHS-20101014/C30
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The objective of this technique is to demonstrate how CSS can be used to replace structured HTML text with images of text in a way that makes it possible for users to view content according to their preferences. To use this technique, an author starts by creating an HTML page that uses semantic elements to mark up the structure of the page. The author then designs two or more stylesheets for that page. One stylesheet presents the HTML text as text and the second uses CSS features to replace some of the HTML text with images of text.
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Where possible, authors should deliver the presentation that does not include images of text as the default presentation. In addition, the control used to switch should be located near the beginning of the page.
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keep reading samples and:
The CSS for the presentation that includes images of text follows. Note that the CSS uses positioning to place the contents of the heading elements offscreen so that the text remains available to screen reader users.


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P.S: Troy McClure: "He was a star in the early 1970s, but his career went downhill:..... I'm younger does not fit.
P.P.S: Sorry for quoting newer version 2. I know w3 does not like to promote it very much ;-)))