The LA Times had a good article yesterday about Dodgers hitting instructor (and former Yankee great) Don Mattingly (here with Joe Torre) who doesn't just believe in planning, but having a plan for "every at-bat."
According to those within the Dodger organization, "Mattingly brings the credibility of having been a great hitter and the work ethic that went with it." Said one veteran player:
"Not many hitting coaches come back from the cage with a sweat, and he does. He puts everything into it, and he's there with you throughout the game. We have some guys who need that credible person staying on them, evaluating on a daily basis, at-bat to at-bat."
"If a guy is pumping strike after strike, you can't just stand up there taking to run up the pitch count. What I saw when I'd see the Dodgers on TV in the first half (when he was on a leave of absence from the team) was easy innings that all looked the same to me, and I'd sit there saying, 'These pitchers can't be this good, we've got to make them work.' A major-league pitcher is going to get his outs, but let's make him earn them. Let's have a plan."
What Mattingly preaches is essentially creating a detailed scouting report for each opposing pitcher, then developing strategies and tactics for attacking the pitcher.