I have gone a couple of times when I was sick, but not because I would be charged, because I only found out very recently that T charges a fee for cancelled sessions (other sessions are not charged, but all cancellations incur a fee, even if the session is cancelled many months ahead). On those occasions when I've been ill I have not shaken hands with T. I have asked him whether he would rather I didn't show up when I'm ill but he has said that as long as I am able to come, he prefers that I do show up.