I get the feeling that had the finished product been polished by Howard that the sentence structure, diction and imagery would have been more complex. Compare these two examples:
As we whirled over the river I saw that it was rushing with terrific velocity. Its roar came up to us, and I saw the seething of eddying whirlpools in its racing current.
Hour of the Dragon
The great river, swerving from those turreted cliffs, swept thunderously through the marching hills with many a rapid and foaming cataract.