I wish I'd this program years ago. Each of us in the small class took away insights that will make a big difference in speed and efficiency.
For me I've make a big increase in stroke length, improved my body position in the water, improved my power phase, and am on the way to rectifying cross over.
As a side benefit, I wasn't even working on tumble turns, but overhearing one tip to a sprinter changed the game for me.