While working on this last table I noted a few other points of interest, but ran out of time before I could investigate them further.
The first point of interest was a question: Given that Kasparov didn't participate in the 1982 USSR zonal, how did he qualify for the interzonal? I found the answer in his book 'Garry Kasparov on Garry Kasparov, Part 1: 1973-1985'. Short answer: he qualified by rating. Longer answer: see the page Zonals 1981-84 (C12).
The next point of interest was a forgotten fact. I had a vague recollection that around the time of the first three KK matches, FIDE tried to shorten the World Championship cycle from three years to two, but I couldn't recall the details. While I failed to find any confirmation one way or the other, I did spend some time reviewing Averbakh's 'Centre-Stage and Behind the Scenes: A Personal Memoir', a book I discussed last year in Averbakh on the World Championship. In it I found the following passage related to the organization of KK2 and KK3.
Averbakh p.221
Both of those book references, 'Kasparov on Kasparov' (p.513, four paragraphs) and Averbakh's 'A Personal Memoir' (p.214), reminded me that I had never really looked into the termination of KK1. Along with two well known essays by Edward Winter,
- Kasparov’s Child of Change (1987) and
- The Termination (1988++),
plus that first Kasparov autobiography,
- Child of Change (Hutchinson 1987, with Donald Trelford),
there are two more recent Kasparov autobiographical sources,
- Unlimited Challenge (Fontana 1990) and
- Kasparov on Modern Chess part 2; Kasparov vs Karpov, 1975-1985 (Everyman 2008).
Although the later discussions of the KK1 termination largely repeat Kasparov's 1987 account, and all three contain a fourth Kasparov account written in March 1985, they still deserve to be reviewed. On top of that, how well do these resources -- Averbakh, Kasparov, and Winter -- square with each other? I'll look at that another time.