> Is it or will it be possible with LaTeX 3 to have standard classes
> (really) do this :
>
> \documentclass[12.37pt]{article}
>
> or
>
> \documentclass[31pt]{book}
>
> ?

This sort of thing can be done with CSS.  Here's the URL for a HTML/XML to PDF tool that understands CSS.
    http://www.princexml.com/overview/

Here's some comments from a user
    http://torrez.us/archives/2008/03/08/561/
(who writes "It sure saved me from using LaTeX.").

--
Jonathan

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