New Delhi, Sept. 20 -- In a rapidly evolving, blitzkrieg format like Twenty20, strategies change every year. And when it's the Indian Premier League, where there is very little to separate two teams, the thinnest margins decide outcomes. Over the last two seasons, those margins have gotten finer and finer with as much as half of the matches witnessing last-over finishes. The average number of balls remaining in successful chases dipped to 8 last year, the first time it has touched single digits since 2009....