Originally Posted by atreides
I haven't seen the first, but from what people post, the 2007 version emphasized what would now be deemed over rotation. If you observe such TI luminaries such as Shinji Takeguchi (???), they rotate to stacked shoulders or nearly stacked shoulders. The new approach emphasizes rotating "just enough" meaning barely exposing the shoulder of the pulling arm. From what I understand, the new approach requires less time between rotations which means that it is capable of generating more speed. Hope this helps.
I would describe the new rotation as more on the order of 45 degrees in either direction. But keep in mind that stacked shoulders weren't what TI taught for freestyle swimming in either DVD. It was for drilling purposes.
The idea behind stacked shoulders was that it would give you a side-to-side balance, thereby making it easier to master a position like fish or skate. The problems with this were that (1) it was easy to overrotate, and (2) it gave swimmers no practice in how to achieve side-to-side balance with the amount of rotation they were actually going to use in freestyle swimming.
Terry began experimenting with having swimmers do fish (now called core balance) and skate with less rotation, and found that it didn't seem to cause them significant problems with mastering side-to-side balance. So that became the new drilling method, and in my experience, it has worked well.
But this is certainly not the only difference in the new DVD! The new DVD begins the process of learning balance differently than the old one did. A few swimmers struggled with the old approach, but I haven't seen any swimmers have problems with the new approach. And there are some new drills that help swimmers to master a top-notch freestyle recovery and entry. I see the new one as a significant improvement over the old one. And that is not to say that the old one was bad - simply that the new one is significantly better!