When it comes to the worlds of baseball and fast pitch softball, the biggest debate is between the old Extension school and the new Connection school.
The Extension school makes their case with pictures like the one below of George Brett.
Extension at the Point Of Contact
However, the fact is that George Brett, and pretty much every good hitter, looks nothing like that at the Point Of Contact on their best swings.
Connection at the Point Of Contact
Connection at the Point Of Contact
If you look at the best swings of the best hitters, you don't see Extension at the Point Of Contact.
You see Connection.
What strikes me about the world of golf is that you can see hints of the same basic argument, the difference being that you can actually find examples of both schools of thought in tour players. For instance, the picture below is a frame from a video clip in which Gary Player compares the swings of Ben Hogan and Tiger Woods.
Ben Hogan and Tiger Woods
at the Point Of Contact
There is a clear difference in the two swings; Ben Hogan is maintaining Connection while Tiger Woods is Extending.
Tiger Woods
Age 16 vs Age 24
What's interesting is if you look at the evolution of Tiger Woods' swing, you can see him move from a classic, Connection-based swing to a very different Extension-based swing as he gets older.
Earl Woods was pretty f'ing smart guy and a keen observer, presumably of Ben Hogan and Jack Nicklaus, among others.