Enkomputiligis Don HARLOW
There is not much to criticize (IMHO) about Jordan's book, which first appeared in 1992. Jordan intended it as both a grammatical and lexical reference, aiming to discuss those points that English speakers might find particularly difficult. So the book is divided into two parts "Esperanto Grammar" (pp. 1 - 118); and "Potentially Troublesome Words" (pp. 119 - 212). Jordan then adds a couple of short appendices about the participles, including matter of primarily historical interest.
The overview "Esperanto Grammar" is eminently readable, and replete with examples. Some of these are taken from Zamenhof; others were created by Jordan himself. It is easy to distinguish between the two types, and not only because of the superscripted 'Z' associated with the Zamenhof examples; Jordan has a tendency to engage in rampant iconoclasm from time to time, a fact which becomes apparent on the very first page of the section with the word he chooses to exemplify the pronunciation of the Esperanto letter ĥ ("bleCH!"). Among the topics on which he spends much time (and examples) are, particularly, (a) correlatives and their use, and (b) transitivity and the use of -ig- and -iĝ-. In addition, a number of pages are devoted to matters which are more customary than linguistic in nature; for example, the X-convention as used on the net, and how to write dates in Esperanto so that they will be understood elsewhere in the world (hint don't use the American system if you're only going to write numbers, since a date like 03/04/00 is at best ambiguous, and so usually incomprehensible outside the United States).
This section is not intended as a textbook for beginners, but IMHO a diligent beginner could read through this in one or two evenings and have a better grasp of Esperanto than he would have had after a month of Teach Yourself Esperanto. But it's certainly not going to be to everyone's taste, in this particular respect.
"Potentially Troublesome Words" concentrates largely on words that may be "false friends" to the native English speaker, and also on words whose usage is not standardized because of cultural differences (see e.g. the section on fraŭlino). One nice thing about this section -- and one of the reasons why it takes up so much space -- is that Jordan gives (a) the correct word, or often words, for the meaning you might mistakenly have attributed to the false friend, as well as the actual meaning of the original word, and/or (b) quite long and complete explanations about the potential problem.
There are a few points on which I would disagree with Jordan -- see in particular "Predicate Adjectives as Stative Verbs", p. 31, (*) and the footnote about the suffix -ec- on p. 97 -- but these are minor quibbles, and I think (as I thought seven years ago) that "this is a book which should be on the shelf of every serious American (and other English-speaking) Esperantist". (Quote from the back of the dust cover.)