A Modern English Grammar on Historical Principles, c.1932. 

               by Otto Jespersen (1860 - 1943) 

Part IV, Syntax, Third Volume, pp. 81-84.

6.4 The pluperfect is used both in main sentences and in subordinate clauses; the conjunctions chiefly used are: when, after, before, till. A few examples of this tense from Stevenson's T may here suffice:

~ examples

After when, the simple preterit can sometimes be used, though the two events mentioned follow one after the other, and the preterit is thus equivalent to a pluperfect.

~ examples

In the following quotation, the use of the pluperfect in the when-clause, where the simple preterit would have been normal, seems to have been induced by the pluperfect in the main sentence.

When they had been little they had watched each other's plates with hostile eyes.

(Shades of Huddleston's, "When Arthur had been a boy he had used to play football". One might wonder who copied from whom. Get the knuckle-rapper.)

This is Exhibit #104 to my assertion that there is at least one past perfect error on any grammar website or in any grammar textbook you can name. Challenges are welcome, encouraged, and appreciated.

.brad.11apr09.