Just watch the recent Coachella video below if any doubts as to how they are doing - so much smiling and touching and laughing with each other, Karl hanging onto Rick's shoulder many times and them singing along together.
Best I've ever seen them interact - can't believe two retirement age lads are putting on a show that energetic, makes me vicariously tired just watching. Amazing.
https://vimeo.com/818174338/8cf3f463...&owner=6216553