I think Leighanne's tweet had to be about his voice. I don't know what else he would be struggling with. He seemed totally fine and normal at both soundchecks and shows I went to - goofing off, being silly, smiling and waving at the fans, etc. He didn't miss a step with his dancing (and they did a LOT of dancing, singing live the whole time!). I don't think there's anything wrong with him physically, other than with his voice. And although I could still hear the hoarseness, he really sounded a lot better live than he has on TV the last few years. As Mare said, his high parts were awesome. Most of the low parts were fine. It's just in the middle of his register - which is unfortunately where most of his solos seem to be - where he struggles.
They did sing "I'll Never Break Your Heart," Mare, and it didn't sound bad, but did he sound as good as he used to singing that song? No. I think that's what breaks my heart (no pun intended) the most about this, is remembering how good it used to be. Judging from Leighanne's tweet, it seems like he is plenty aware of that, too, even though no one's openly addressed it. I hope they do when they feel the time is right, but I love and support him no matter what. He could stop singing altogether and just stand on the edge of the stage and goof around and wave at fans, and I would still go to see him. I love his voice, but I love him for so much more than that; it's not the only thing that defines him.