I am a golf product of a tennis family. When the family went on vacation, everybody hit the courts, and I hit the course. I played golf and tennis in high school, and then went on to golf in college (before I gave it up for riflery as it were…).
Then I grew up and became a really mediocre golfer. Later in life, I became a really mediocre tennis player. When arthritis started to set in, I gave up competitive tennis and started playing golf again. I went to a golf pro (at Palm-Aire in Pompano Beach) and he pointed out that my power swing was eerily reminiscent of a tennis player, especially the leg and hip action. He encouraged me to cultivate that action, as it was particularly difficult to teach unless it was already there.
Looking back at it, it would appear that the tennis work I put in as a mid-lifer germinated into my later life golf game, and intrinsically corrected a number of faults that had doomed my game years earlier. If for no other reason than to understand the dynamics of mid-body movements and development of “power” with legs and body mass, tennis movement is worth at least a modicum of study by any serious student of golf.
Interestingly, Jack Nicklaus became a serious student of tennis later in life once his schedule began to allow for it.