Just like in Bleach the only way Aizen could be beat is if he stopped using his most special and amazing power. Same with Obito. Kishi wrote himself into a corner. I called this a long time ago. Well I hoped that I would have been wrong. Still have not read the re-scan yet but I assume you are right and I was expecting it to come up eventually. I truthfully don't think there is a logical explanation. Kishi just wanted to get rid of that ability. This is very disappointing.