From mid-1993 (while he was still an amateur) until 2004, Woods worked almost exclusively with leading swing coach Butch Harmon. From mid-1997, Harmon and Woods fashioned a major redevelopment of Woods' full swing, achieving greater consistency, better distance control, and better kinesiology. The changes began to pay off in 1999. Woods and Harmon eventually parted ways. From March 2004 to 2010, Woods was coached by Hank Haney, who worked on flattening his swing plane. Woods continued to win tournaments with Haney, but his driving accuracy dropped significantly. Haney resigned under questionable circumstances in May 2010 and was replaced by Sean Foley.
Arnold Palmer Invitational presented by MasterCard: Birdied the 72nd hole to beat Sean O'Hair by one stroke and claim his sixth Arnold Palmer Invitational presented by MasterCard. Sank a 15-foot birdie putt on the final green, duplicating his last-putt heroics from two previous years (2001, 15-foot birdie putt to beat Phil Mickelson; 2008, 24-foot birdie putt to beat Bart Bryant). Matched his largest comeback after 54 holes (five strokes) with his victory. He also came back from five strokes behind after 54 holes to win the 2000 AT&T Pebble Beach National Pro-Am (Mark Brooks and Matt Gogel). Out of 66 career wins, it was his 19th coming from behind. Became the first player to win six Arnold Palmer Invitational titles. The only other players with multiple victories at the event are Tom Kite (1982 and 1989) and Loren Roberts (1994-95).
Woods was raised as a Buddhist, and he actively practiced his faith from childhood until well into his adult, professional golf career. In a 2000 article, Woods was quoted as saying that he "believes in Buddhism... not every aspect, but most of it." He has attributed his deviations and infidelity to his losing track of Buddhism. He said, "Buddhism teaches me to stop following every impulse and to learn restraint. Obviously I lost track of what I was taught."
Woods collaborated closely with TAG Heuer to develop the world's first professional golf watch, which was released in April 2005. The lightweight, titanium-construction watch, designed to be worn while playing the game, incorporates numerous innovative design features to accommodate golf play. It is capable of absorbing up to 5,000 Gs of shock, far in excess of the forces generated by a normal golf swing. In 2006, the TAG Heuer Professional Golf Watch won the prestigious iF product design award in the Leisure/Lifestyle category.