I too have dealt with a few aged radixes. They are so special.
Inactivity and lack of strength are clear signs. I've also noticed a contentment(as I call it) with them. My last aged snake was my friend Scar. I still miss that old man.
The time we spent together was priceless. I wish I would have had more time.
A flood of memories have just hit me and I need a break.
He was a great radix.