This is an eye-opening expose of Men's professional tennis in the early 1980's. As such, it is dated in some respects. The WCT tour is long gone, appearance guarantees are no longer banned, and there are some other aspects of the tour that are perhaps more professional then they were back then.
But as he notes in the 2011 afterward, many if not all of his concerns are still quite relevant, such as questions about drugs, and it may be more of a concern now that it was back then with things like EPO and a drug testing regime that is not up to par with cycling, track and field, and other sports. Tanking still happens. Concerns about gambling are even more relevant now, and so on.
Some of his charges and concerns may seem far-fetched and overblown to some, but apparently Bud Collins and Arthur Ashe didn't think so. In general, he points out things that tennis people (whether insiders or fans) just take for granted are considered outrageous (if not illegal) in other sports and subject to investigation.
A few additional thoughts:
1. He makes at least a couple of remarks about homosexuality on the tour, and the fact that no one would talk to him about it. Did he have reason to believe it was widespread? Was this a stereotype carried over from the Bill Tilden era? Or was he attempting to allege that there was a double standard with the stereotype (especially at the time) that many if not most female athletes are lesbians?
2. With all of the ink spilled about conflicts of interest, the author admits to cheering for a player he was friendly with during one of his matches, with no apparent sense of irony or self-awareness. Sure, he wasn't exactly a part of the tennis establishment, (and he ensured he never would be with this expose) but he was there on an AP press credential nonetheless.
3. He points out that spectators are expected to remain silent during the points (and avoid the kind of heckling that is common in other sports) in keeping with longstanding tradition but at the same time, the decidedly nontraditional antics of Connors, Nastase, and McEnroe were tolerated and even celebrated.
4. The author's outrage about exhibitions being fixed or arranged struck me as a bit naive at first. I knew or suspected that they are arranged (at least to the point of them often going to 3 sets) when I was in my early teens. (Who wants to go to an exhibition and see a 6-2, 6-1 match?) But apparently professional tennis gained a reputation of being fixed or "fake" during the pre-open era (pre-1968) with it being considered hardly more legitimate than professional wrestling. There are also legitimate concerns if an event is billed as "Winner take all" or something similar.