Complex sentence: After the fiasco of 30 June, Haking wrote that the 39th Division had been in France since March and lacked offensive spirit; the attack on the Boar's Head had led to a great improvement in the fighting value of the division.
Split into simpler sentences: After the fiasco of 30 June, Haking wrote that the 39th Division had been in France since March and lacked offensive spirit. The attack on the Boar's Head had led to a great improvement in the fighting value of the division.