This paper is a bit short on facts. Gen. Harbaksh Singh has said many other things in his memoirs. Yes the general was late to be made aware that Pakistani 1st Armoured Division is located close to Khemkaran forests just across the border. That was an intelligence failure. In spite of this handicap he put together a stout defensive strategy in just five days. This included;
1. Deny the invading force the roads, hence strong defensive positions were built on roads, leaving only sugarcane fields open for the invading force.
2. He knew that the invading force denied of roads will take to the sugarcane fields, hence he flooded them a day before
3. Some of the enemy tanks were brand new, the soldiers had not fired their guns from them, Gen. Harbaksh knew that and used their inexperience to his advantage to allow them come very close. When push came shove, the Pakistani crew fumbled at the last minute to load their guns. In the meantime, highly trained Indian gunners zeroed on them with good advantage.
4. Pakistanis used their tank force in a piece meal manner. That ruined their advantage of mass formation. Well, that allowed them to walk into General's U shaped defensive formation, a trap copied from Roman general's tactics.
With all these tactics, there was only one outcome, victory for Gen Harbaksh Singh and India.
Read more about it 1965 an Israeli analyst Leo Haiman's analysis of Pakistani failure in US Magazine - Military Review - February 1966.