My MIL rallied on her deathbed, which gave us so much false hope that she might not be dying. It was miraculous. She gave a stand-up show that rivaled Rosanne Barr--she literally "roasted" each of us standing around her bedside, in a kind and funny way. I, too have heard from hospice workers that it is not uncommon to have a final rally.
But frankly, TMS, I'm really amazed that your friend actually went out to eat at his last rally!!