By the same token, don't use this mantra to use low-contrast text like that used with this article. Absolute black may be a no-no, but this doesn't mean all of 'dark' is a no-no. Low-contrast text is poor form.
WCAG 2.0 requires a contrast of 7:1 to reach AAA levels. [1]
you can test it yourself with a bunch of tools but I couldn't find link to results on any of them [2][3][4].
[1] http://www.w3.org/WAI/WCAG20/quickref/#qr-visual-audio-contr...
[2] http://webaim.org/resources/contrastchecker/