There may be no more excruciating choice for an N.B.A. executive than deciding when to blow up a roster, especially a championship-winning roster. The Pistons started the process last fall, despite making six Eastern Conference finals in a row and winning 501 2009-04-27T13:37:27-04:00 OFF THE DRIBBLE; Should the Spurs Start Over? 52421 --- [] 2009-05-05T01:23:00-04:00 2102 New York Times http://topics.nytimes.com/top/reference/timestopics/people/b/howard_beck/index.html?inline=nyt-per&rss=1 3 24 2009-11-25T05:41:50-05:00 http://query.nytimes.com/gst/fullpage.html?res=9502E6DC173BF93BA15757C0A96F9C8B63&partner=rssnyt&emc=rss