Wanted to come back and chime in on this Richard discussion...

I like your theory. I think part of that COULD happen through the TA storyline but only part. I think, if you really wanted Richard to feel 'jealous' or upset that the TA is 'teaching' (Which we don't know for sure...TA's teach tutorials, not lectures, and they're STUDENTS, not professors), I think it would be because the department lets him go, since they don't need him, or because they think he's ill and needs to retire. He sees the TA teaching in a class, and thinks about how he wants to be doing that, but he's no longer allowed to.

A TA wouldn't threaten Richard necessarily, IMO. If you know the workings of a university/college, a TA would RARELY, if ever, teach a lecture (TA's are grad students with their own studies, usually...they're not professors). Lectures are taught by the professor. Tutorials are classes where you can go over the lecture material in a class setting, and those are run/taught by TA's.

Very different jobs. A TA can't take Richard's position because a TA doesn't have the credentials for the position. YMMV

BUT, of course, forgetting my nitpickiness on who can be a lecture prof and such, I totally agree that this provides a great opportunity for the writers to show the impact the illness has on Richard's self esteem - He sees the TA teaching...it's a blow to Richard because it reminds him that he's no longer young, youthful, and he's no longer being asked to work. Seniors tend to feel a huge sense of loss when their 'rights' (well, their career identities) are taken away from them. Even though Richard still has his company, if they don't ask him back as a guest lecturer, he'll feel like he's slowly being refused and rejected in being a career man in society. Did he like retirement the last time?