I wonder how much paper would be saved around the world if Word shipped with
default margins of 1cm instead of 1 inch. If someone would pay me for all the
paper saved, I've got a feeling I would be a wealth [man/woman/person].
There may be some truth in that (and in fact it's more than you say,
as the default side margins are 1.25 inches), but the default margins
weren't chosen frivolously.
The important measurement isn't the margins, but the width of the text
column. A column that's too wide in proportion to the font size is
difficult to read. When the eye has to scan too far horizontally, it
tends to lose track of which line you've just finished reading and
where the start of the next line is. The default margins on US Letter
paper allow a text column 6 inches wide, which is just about at the
readability limit for 12 pt body text.
If you really want to save paper, set up your standard document
template for two columns, each 3.125 inches wide, with 0.75" side
margins and 0.75" between the columns. You could also reduce the
default font size to 10 or 11 pt. Don't do this to Normal.dot, though,
because it will mess up labels printed from the Label dialog. Also set
your printer to default to duplexing, and save ink by printing in
draft mode...
