This quote is from Mark Alarie who played on coach K's first teams in the mid-80's. It was in SI.
"He had every drill written down to the minute, and on the practice plan he would write the reason why we were doing it.He would explain that this is what the other team is going to do and then prepare us for it.I'm telling you, I played basketball all my life, I spent five years in the NBA. I never had a coach put one-tenth of the elbow grease into constructing a single practice as Coach did for everyone of those practices."  
It would be enlightening to observe one of our practices...