Sorry, West Coast, but I have no direct knowledge of what went on in the H-blocks - except that 'Internment without trial' caused sufficient resentment amongst the population for many to rally to the IRA cause.....
There probably were a few sadists acting very improperly there, just as there clearly are in Iraq.
One amusing piece of Anglo-American misunderstanding some years ago was that MacDonalds (who, I understand, sell things called 'burgers') were making compulsory IRA deductions from employee pay. This caused howls of anguish - until it was explained that they were for Individual Retirement Accounts, not the Irish Republican Army!