Figured it out.

Don't go to 'page layout', go to 'Home' which is the large button on
the LHS.

Middle of the screen there is a button with a doubleheaded arrow to
the left of some bars. Hit that.

Go to line spacing options.

Up to now I have been punching radio buttons, but you don't have to do
that. Set the two 'before' and 'after' spacing box to zero. I have
even managed to get new .docs to give single spacing.

If I was going to write stupid front ends to software, I would make
sure that there is always a command line interface for that software,
so that when all else failed, you can just give it the command from
the command line, without having to surf through lots of badly named
and badly grouped menus.

set linespace currentdoc nil

set linespace normaltemplate nil

This way, however hard you try to screw up the front end, someone can
always get some work done in spite of you.

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