My thoughts follow.
I would have preferred to learn that our bishops have multiple and robust lines of succession. A 91% bottleneck implies an oppressive group think that tolerated only a single point of view. After all, there were twelve apostles, why are so many lines snuffed out? Yet the underlying facts do not support a grand conspiracy to muzzle and control. Pope Benedict XIII (of the Rebiba line) preferred to consecrate bishops himself. His new bishops from the early 1700s were disbursed out to new frontiers all over the world, and those frontiers had explosive growth. These new bishops consecrated their own successors because of logistics -- there was no British Airways service for other apostle lines to pop in and out for frontier area ordinations.
The undocumented status of Rebiba's consecration means we cannot be sure that our lines of succession to the apostles are intact -- this is clearly the Holy Spirit's doing. Doubt diminishes ego-driven certainty, and requires constant communion with God to monitor the steps we take. Thus, I think we can expect our episcopacy to overtly manifest charism and grace to re-assure us that they really are successors of the apostles.
