Their primary conclusion was that while the rams succeeded in partly shearing through the drill pipe they failed to seal the bore because the drill pipe had buckled out of the intended line of action of the rams (because the drill string was caught at a tool joint in the upper annular BOP valve), jamming the shears and leaving the drill string shear actuator unable to deliver enough force to complete its stroke and fold the cut pipe over and seal the well.
Their primary conclusion was that while the rams managed to partially shear through the drill pipe, they failed to seal the borehole because the drill pipe had bent out of alignment (the drill string got stuck at a tool joint in the upper annular BOP valve), jamming the shears and preventing the actuator from generating enough force to complete its stroke and fold the cut pipe over and seal the well.