Complex sentence: The commander-in-chief never reposed in him the confidence that he gave to Beresford, Hill and Robert Craufurd but in the resolute, thorough and punctual execution of a well-defined task Picton had no superior in the army.
Split into simpler sentences: The commander-in-chief, it is true, never reposed in him the confidence that he gave to Beresford, Hill and Robert Craufurd. But in the resolute, thorough and punctual execution of a well-defined task Picton had no superior in the army.