It could be something physical. My sense was it was something else in Lee's case: a change in his routine. I think the routine of coming into work kept him in a

It could be something physical. My sense was it was something else in Lee's case: a change in his routine. I think the routine of coming into work kept him in a pattern that kept him from deteriorating quickly (or, at least, kept us from recognizing his deterioration). When he had heart surgery, he took several months off to recover. When he returned, he seemed dramatically different. I also noticed a dramatic change immediately after he took time off for his wedding/honeymoon. And, after he left Cloudflare, the article talks about how it seemed like the effects of the disease accelerated. I'm not a doctor, and there very well may be some other connection, but my sense in this case was the routine of work actually allowed him to hold the effects of the disease off and, at those times when he didn't have it, those effects accelerated.