[Groff] Confused over diversions

[Clarke Echols]

I am attempting to understand how diversions work, but
I am getting results that don't match the examples in the
info file.  I put a little test file together based on the
example in the info file, but things get re-ordered so it
looks like the text in the line before the first
'.di xxx' line ("Before the diversion.") is also diverted.
What is going on here?

I am using groff 1.18.1 running in Cygwin on a Windows 98 machine.

Here is the source file and what I get (using Cygwin's nroff but
groff gives the same result, just in a different typeface).

Input file:
===========
> .ft C
> .sp |2i
> .ll 4.5i
> Before the diversion.
> .di xxx
> 1 Inside the diversion.
> 2 Inside the diversion.
> 3 Inside the diversion.
> 4 Inside the diversion.
> 5 Inside the diversion.
> 6 Inside the diversion.
> 7 Inside the diversion.
> 8 Inside the diversion.
> 9 Inside the diversion.
> .br
> .di
> After the diversion.
> .br
> Now we're going to do some other stuff here.
> .br
> And another line.
> .sp 1v
> Then a blank line plus a new line of text.
> .br
> .xxx
>
Printed result:
===============
>
> After the diversion.
> Now we're going to do some other stuff  here.
> And another line.
>
> Then a blank line plus a new line of text.
> Before  the  diversion.   1 Inside the diver-
> sion.  2 Inside the diversion.  3 Inside  the
> diversion.  4 Inside the diversion.  5 Inside
> the diversion.  6 Inside  the  diversion.   7
> Inside  the  diversion.   8 Inside the diver-
> sion.  9 Inside the diversion.

I have another question, but I'll save it for later.

Thanks,

Clarke