Checkpoint 3.4 relative vs absolute

http://www.w3.org/WAI/wcag-curric/sam32-0.htm written by Chuck Letourneau
states:
"For example, in CSS, use 'em' or percentage lengths rather than 'pt' or 'cm',
which are absolute units. If absolute units are used, validate that the rendered
content is usable by checking the results on various browsers or systems."

This is confusing.  My interpretation of 3.4 is that even one instance of an
absolute value will result in failure to meet the checkpoint.  However, the
above seems to suggest that I can still meet the checkpoint provided I have
tested that the output (which relies on absolute values) is usable.

Please confirm that absolute values in a CSS file still pass checkpoint 3.4 as
long as I've validated that the rendered content is usable.

We're OK with relative font sizing but have yet to achieve the desired results
for positioning of block elements with relative lengths and still rely on pixel
widths for navigation bars etc.

Regards
Michael Virant
email: virant.michael.w@edumail.vic.gov.au



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