I would agree if George actually could not play at that level anymore, but did you actually watch the videos I just posted? That was from 2 days ago...does not sound too "old and slow" to me. He appears to be in great shape physically still, had as much energy as I remember from back in the day, and while not completely in the pocket on some of the solos, he was ripping through a lot of it (sounded just slightly unrehearsed in a few parts versus actually struggling). And also again, he's playing through a high gain rig that fits those songs and lets him really tear into them.
George would always get a "pass" from me if he needed it, but I'll keep saying I don't think he needs it...I think he mostly has all those old chops, he just doesn't always dig being an 80's shred guy. Also, he's not 70 yet, he's 66, and even 70 for an in shape guy isn't remotely that crazy old. He looked to me there like a guy half his age in terms of physical shape and bouncing around on stage.
What I've seen more over the years is just different moods/phases he goes through that aren't the classic shred, and he's not the most consistent player live to begin with.