There was good reason for the employment of this large proportion of cavalry in an operation that was to be carried out in country most unsuited for mounted work.
General Allenby was always reluctant to keep his mounted troops in the trenches, if he could avoid doing so. Cavalry are most uneconomical troops in trench warfare, since at least a quarter of them are occupied caring for the horses, and consequently are not available for the firing line. Moreover, while employed in the line, they are deprived of the opportunity of training for mounted work, and their horses generally lose condition, since there are not enough men to look after them properly.
When, however, the three cavalry divisions were not used in the trenches, there were barely sufficient troops left to hold our long line securely, and very few infantry could be spared for extraneous enterprises. Moreover, though he would not put his cavalry into the line, if he could help it, the Commander-in-Chief had no intention of allowing them to grow rusty for lack of active operations. He was a firm believer in the old prize-ring adage that the best training for a fight is fighting.
The enemy's position ran north and south, astride the Jericho-Amman road, just west of Shunet Nimrin, his left resting on the deep gorge of the Wadi Kefrein, and his right flank thrown back in a half circle across the Wadi Arseniyat track to El Haud. Both flanks were protected by detachments of cavalry. From Shunet Nimrin two roads led back to Amman; the metalled road through El Salt, and the more direct track through El Sir. The former was the only one available for wheeled traffic, but the latter had been considerably improved by the Turks since our last raid into Gilead. The plan was for the infantry to attack this position from the west, with the New Zealand Mounted Brigade on their right flank, while the rest of the cavalry, moving along the east bank of the Jordan as far as Umm el Shert and Jisr el Damieh, turned into the hills up the tracks from these two places, and captured El Salt, thus cutting the road to Amman. The Beni Sakhr Arabs undertook to hold the Ain el Sir track. With their only two lines of reinforcement or retreat thus closed, there appeared to be a good prospect of capturing or destroying the enemy forces at Shunet Nimrin.