I am very grateful to Professor William Slater for his review in BMCR 2007.05.18 of CLGP I.1.4, and especially of the section on Aristophanes edited by Elena Esposito (lexica) and me (hypomnemata and marginalia). I would like to offer a short reply on some "Didymean" points, for the benefit of the BMCR reader.
The hazardous definition of Didymus the Great as a "student of Aristarchus" is not mine: it appears in the argumentation put forward by K. McNamee (Marginalia and Commentaries in Greek Literary Papyri, Diss. Duke University, Durham 1977, p. 189, which I quote on p. 161 n. 22) in favour of the hypothetical Didymean authorship of the hypomnema from which P.Oxy. 2737 (= CLGP 27) arose. I apologize for quoting it in a footnote without careful comment or explanation. My aim was not to subscribe to any presumed relation between Didymus and Aristarchus, but to provide opinions consistent with the idea that P.Oxy. 2737 sprang from Didymean exegesis.
Readers will judge whether this idea, as the reviewer argues, is uncritically indebted to assumptions of 19th-century scholarship concening the role of the Chalkenteros in the transmission of ancient exegesis (and lexicography).1 I would merely emphasize that on one hand it is based on the little we actually know about the history of explanation of Aristophanic comedy in Hellenistic and Roman scholarship;2 on the other hand, it rests on the evidence from the papyri involved (P.Oxy. 2737 as well as P.Flor. 112 = CLGP 28, both hypomnemata): i.e. internal terminus post quem (as a quotation of Aristarchus in the former, of his contemporary Kallistratos in the latter), open mention of Didymus (P.Flor. 112, frr. CDE s.l. 10 and mg. inf.), and learned appearance, despite epitome (see my introductions ad nrr. 27 and 28).
Finally, it is not at all odd if my entry "Didymus" in the "Lessico dei Grammatici Greci Antichi" includes no fragments from the grammarian. As explained in the website homepage, "the files concerning some particularly important grammarians, who call for a more extended and complex encyclopaedic entry, are made available for download as they are filled in with the updated bibliography alone, while the general discussion and possible texts will be added on in a second phase. This approach is planned for Aelius  Herodianus, Apollonius  Dyscolus, Aristarchus, Aristophanes, Didymus, Eratosthenes, Galenus, Iulius  Pollux, Zenodotus". Didymus is now at the second step out of three: bibliography and outline, without texts for the moment--understandably, I hope.
1. See, for example, the re-appraisal of Didymus by P. Harding, Didymus: on Demosthenes, Oxford 2006, pp. 31-39, 41.
2. More recently S. Trojahn, Die auf Papyri erhaltenen Kommentare zur Alten Komödie. Ein Beitrag zur Geschichte der antiken Philologie, München-Leipzig 2002, pp. 117-152, whose I discussed some details in "L'esegesi ad Aristofane su papiro", in Interpretazioni antiche di Aristofane, a cura di F.M., Sarzana 2005 (then Rome, Edizioni di Storia e Letteratura, 2006), p. 9 n. 39.