Lucy Chester, a visiting fellow at the Center for International Security and Cooperation at Stanford University, describes the flawed process of drawing the Punjab boundary award.
Link to artivle: http://www.unc.edu/depts/diplomat/archives_roll/2002_01-03/chester_partition/chester_partition.html
India's partition was flawed in several major ways. The most significant error, for which all parties must share responsibility, was misguided reliance on a best-case result, combined with consistent refusal even to acknowledge the possibility of a worst-case outcome. Mountbatten and the rest of the interim Government of India ignored repeated warnings from Sir Evan Jenkins, the highly respected Governor of the Punjab, that the division would result in large-scale violence.
In addition, the architects of partition refused to provide a sufficiently prolonged timetable to allow for
1) the necessary geographic surveys and other information gathering, for2) boundary demarcation (the process of fixing boundary markers on the ground), for3) public announcement of the new line, and for4) transfer of populations, if necessary.
If they had provided more time for government institutions and local communities to absorb and adapt to the implications of the Radcliffe award, the level of violence might have been lower—and the authorities’ abilities to impose law and order higher.
In their rush to achieve their own political goals, British India’s most powerful parties decided not to complete territorial partition before final political separation. This decision left Indian and Pakistani citizens in the peculiar predicament of not knowing which country they were in on August 15 or 16. Additionally, Mountbatten’s delay in announcing the Radcliffe Line meant effectively that India and Pakistan had no boundaries for the first two days of their existence. Even if the award had been announced a few days earlier, provincial and local officials would not have had enough time—particularly in the demanding circumstances they faced—to make the necessary administrative arrangements.
As a side note, here's New York Times article, dated June 3rd 1947, on Lord Mountbatten's plan to partition India.