I'm trying to do a layout that consists of a series of tables on two-column
pages in landscape mode. I want to keep all lines of all tables together.

The first problem is that the check mark for not breaking tables doesn't
seem to apply to column breaks, only page breaks. (table properties, row,
options, 'allow row to break across pages').

So my alternative would seem to be inserting column breaks manually between
various tables. This is, of course, a crummy solution because it requires
manual reformatting every time a table gets more or fewer rows.

But even worse, the column breaks don't work like page breaks. That is, if I
turn on paragraph marks and insert a page break, I see a line (for the page
break) followeed on that same line by a paragraph mark, and the table
following that paragraph mark starts at the very top of the next page.
However, if I instead insert a column break, the column break line is on a
line by itself, and there is a paragraph mark at the top of the second
column. This causes the table to start a line lower in the right hand column
than the left hand column.

I saw some advice about making paragraph marks single pixel high with zero
line spacing, I suppose I should try that, but this is very very unintuitive
and painful. It is actually easier just to bang on the enter key and insert
blank lines, and no less manual to maintain that as table sizes change.