[DougBTX]

Just pulling quotes from the Wikipedia page, "he avoided complicated syntax and about 70 percent of the sentences are simple sentences — a childlike syntax without subordination."

Subordination is the key word, ie, limiting the amount of nesting. That's why the for quoted above is out, since there are two statements and an expression nested inside the for statement (i=2, i<size, and i++), and there are two sub-expressions nested inside the push call (result[i-1] and result[i-2]).

Going out on a limb, I'd say Hemmingway's writing is building up complex narrative using simple building blocks. The body of the for loop above is a single line, which does simple arithmetic, array indexing, and a method call all together. In contrast, each line in the while loop body does roughly one thing: first addition, then assignment, assignment again, then a method call.