git pretty format: "%+b" not working with "%w" in front of it?

[Robert Dailey <rcdailey.lists@xxxxxxxxx>]

I have the following log:

$ git log

commit 7ffb909bb8f38607e3d6d9f3504a66ca978f0ac2
Author: Robert Dailey <robert@xxxxxxxxx>
Date:   Mon Dec 12 11:01:00 2016 -0600

    Add initial skeleton files & a few interfaces for new kizi/sc16 stuff

    This is still FAR from complete....


I want to generate changelogs, using github markdown list format. I
tried doing that using this command:

$ git log --pretty=format:"* %s%n%w(100,2,2)%+b"

However, the 2nd newline is not inserted:

* Add initial skeleton files & a few interfaces for new kizi/sc16 stuff
   This is still FAR from complete....

The format I'm expecting is:

* Add initial skeleton files & a few interfaces for new kizi/sc16 stuff

  This is still FAR from complete....

This seems to work, but I do not get the 2-space indentation required
to continue text on the current list item:

$ git log --pretty=format:"* %s%n%+b"

* Add initial skeleton files & a few interfaces for new kizi/sc16 stuff

This is still FAR from complete....

So why isn't it working when I use %w before the %+b? Am I doing
something wrong? Note I'm using git version 2.10 on Windows through
Git Bash.