some of the huge tables which in my original sources spread
over two book pages, appear truncated by the PDF, no matter
what papersize I try to set (e.g. like A3).
The default column separation is 3 ens. We can make the table
a bit narrower by reducing this to 2 ens,
lb2 s2 s2 s2 s2 s2 s2 s2 s2 s2 s2 s2 s2 s2 s2 l
and then the table does fit within the width of A3 landscape,
as the attached example shows.
(This was formatted with mm which supports multi-page tables
with repeated headers. I also messed with the vertical
spacing around the horizontal lines a bit. I first tried
to add .sp requests before and after the horizontal lines,
but then the last line that should have been on the bottom
is always pushed to the next page. So I gave up and added
extra-linespace requests using \x instead.)