Yes, he can, if he’s in the beginning stages. Besides, of course my speculation is without evidence. That’s why it’s called speculation.
Yes, he can. But he may have an inkling what’s coming and be preparing for it.
Alzheimers isn’t the only possibility either. Some are guessing that maybe it’s congestive heart failure that’s the problem. I remind everyone that diagnosis at a distance by amateurs is a fool’s errand. None of us really know what his medical status is, and can only see some symptoms—weight loss, etc.