More (as I posted earlier)

From HRW

The protection and treatment of captured combatants
during an international armed conflict is detailed in the Third
Geneva Convention relative to the Treatment of Prisoners of War,
which defines prisoners of war (POWs) and enumerates the
protections of POW status. Persons not entitled to POW status,
including so-called "unlawful combatants," are entitled to the
protections provided under the Fourth Geneva Convention relative
to the Protection of Civilian Persons in Time of War. All
detainees fall somewhere within the protections of these two
Conventions; according to the authoritative Commentary to the
Geneva Conventions of the International Committee of the Red Cross
(ICRC): "nobody in enemy hands can fall outside the law."

There are other international legal instruments outside the
Geneva Conventions that also affect the treatment of persons
during armed conflict -- and after the conflict. While some human
rights standards can be derogated or limited during times of war
or national emergency, other human rights standards continue to
apply in full force at all times. Instruments relevant to the
treatment of persons deprived of their liberty detainees include
Torture and other ill-treatment of detainees is prohibited as a
matter of customary law and treaty. Article 7 of the International
Covenant on Civil and Political Rights, and which the United
States ratified in 1992, provides that "No one shall be subjected
to torture or to cruel, inhuman or degrading treatment or
punishment." Also in force at all times is the Convention against
Torture and other Cruel, Inhuman or Degrading Treatment or
Punishmentand the UN Standard Minimum Rules on the Treatment of
Prisonersto which the United States became a party in 1994.

If I read that right, the Human Rights Watch interpreation is a little different from the DOD.
On the one hand, you are right - the DOD policy basically grants them GC rights.
However, if all one has heard are the admin soundbites (i.e. We consider the detainees to be unlawful combatants and thus the Geneva Convention does not apply), then the average Joe may be forgiven (a little) for thinking that anything goes.