[Groff] Aligning Poetry on Facing Pages

[Paul O'Leary McCann]

I recently made an open offer to some friends to make some books for
them; one of them requested a copy of Jubilate Agno, which you can find
here.

http://www.pseudopodium.org/repress/jubilate/

If you take a look at some of the sections, you'll notice that (using
frames) lines from different fragments are laid out opposite each other.

In print this would mean that each line would have a mate on the facing
page. Since the lines are not generally the same length, I have trouble
figuring out how I'd manage to do this in groff. I've come up with some
ideas, but they're all more sophisticated than anything I've done
before. 

Has anyone ever done anything like this? What's a good way to accomplish
this? -POLM