How is Trooper Warren while "out of the saddle"?

From the text:

Trooper Warren was not a good horseman – I could tell that the minute he mounted me. He was always tense and rode me heavy in the saddle like a sack of potatoes. He had neither the experience and confidence of Corporal Samuel Perkins nor the finesse and sensitivity of Captain Nicholls. He rocked unevenly in the saddle and rode me always on too tight a rein so that I was forced to toss my head continuously to loosen it. But once out of the saddle he was the gentlest of men.