> This also raises the question of whether a paragraph-at-once
> algorithm could handle such single-line adjustments without being
> unwieldly or slow. I've never been able to get this kind of
> precision in TeX, as I've mentioned before; it's much faster to do
> it in groff.
My guess is that combining both approaches at the same time is neither
useful nor easy to implement. However, I could imagine that using a
diversion you can `catch' a TeX-like formatting of a paragraph; with a
kind of `line number request' you could then do `Increase/Reduce word
spacing in line 3 by reducing/increasing letter spacing' if necessary.
Whatever to implement, this needs a lot of research. You might look
up literature to the theme `microtypography' (probably also using the
keyword `TeX') to get more information.
Note that with luatex, such manipulations are already possible: It
allows direct access to the formatted paragraphs in a programmable way
(using lua).
Werner
