Quite the contrary. The Marine's testimony will be quite consistent with an environment which is suitable for the treatment of a prisoner of war accused of treason.
The conditions were not consistent with the presumption of innocence and protection of citizen rights which are implied by the legal treatment which Lindh is receiving in court.
The venom which is contained in the many replies concerning Lindh reflect the general feeling that Lindh deserves to be punished for treason.
The defense is far ahead of the game if they are successful at demonstrating that the treatment and charges against Lindh constitute a charge of treason. The Constitution is very clear about the level of proof required and it exceeds that which is typical in criminal cases.
Like it or not, we are trying Lindh for having committed treason and we are unwilling to admit it. I predict that we will be hearing from the US Supreme Court about this at some time in the future.