Comment 26 for bug 1006743

"Neither Breaks nor Conflicts should be used unless two packages cannot be installed at the same time or installing them both causes one of them to be broken or unusable. Having similar functionality or performing the same tasks as another package is not sufficient reason to declare Breaks or Conflicts with that package." <http://www.debian.org/doc/debian-policy/ch-relationships.html#s-conflicts>

So we shouldn't use that to communicate the incompatibility of dns proxy and dnsmaq.

"Keep usage notes to what they belong: the NEWS.Debian, or README.Debian file. Only use notes for important notes which may directly affect the package usability. Remember that notes will always block the install until confirmed or bother the user by email." <http://www.debian.org/doc/manuals/developers-reference/best-pkging-practices.html#s6.5.1>

This is what I've done anyway. But I'm against touching something that belongs to another package. That should be left up to the user.