B.L. Gildersleeve, review of Sophokles Elektra. Erklärt von Georg Kaibel
(Leipzig: B.G. Teubner, 1896), in American Journal of Philology
18 (1897) 353-356 (at 353):
"Exhaust interpretation before you attack the text" is a wise rule of a great teacher, but, unfortunately, the interpreter too often becomes exhausted before the interpretation and conjectural criticism is summoned to the relief. To be sure, what is sometimes called conjecture is not, properly speaking, conjecture. It is a manner of proof-reading for which modern slaves of the vernacular press take no credit to themselves, as every man that has served in the humble capacity of reader makes daily 'emendations' that would be the fortune of some scholars, if the operations were performed on the body of the classic texts. It is purely a matter of familiarity with the range of thought and expression, and is less a wonder, the more one is at home in a given language.
The "great teacher" was Friedrich Ritschl. Gildersleeve elsewhere stated the rule as "Don't go into criticism until you exhaust hermeneutics." See Maxims for Philologists