At least 25 years.
A history of Tiger Woods' swing coaches
- Butch Harmon (1996-August 2002)
- Tiger Woods (September 2002-February 2004)
- Hank Haney (March 2004-May 2010)
- Sean Foley (August 2010-August 2014)
- Chris Como (September 2014-December 2017)
- Tiger Woods (January 2018-Present)
Sorry, my comments got cut off when I originally posted this. My point is that swings aren't ever "fixed" or static. I don't think there is a perfect swing in golf, baseball, tennis, etc.... There is an optimal swing for an individual at a point in time. A professional is always tinkering and trying something new to adjust to the adjustments that have been made against him or her.