The idea that Derek Jeter can somehow shorten his stroke or change his batting stance in order to restore some of his lost effectiveness is ridiculous.
Baseball players, like most athletes, achieve success by optimizing every aspect of their game until they are competitive with the best athletes in the world in their sport. This happens in their late teens and early 20's. By the age of 30, most athletes are in decline.
There is nothing for Jeter to find in his batting stroke or his stance, or his head, or his diet, or his preparation, or his discipline, or anything. Jeter lost his real effectiveness years ago. Like Cal Ripken, he was allowed to trade his moderately decent offensive skills for a few more cycles in the field and the illusion of defense. The illusion of defense is easy. Nobody knows if you should have had that runner at first but didn't because you were too slow, or your arm was too weak. Nobody knows if you should have reached that ground ball to the left that got through. Nobody knows if you should have been able to turn that double play. All the average fan knows if whether or not you fumbled the ball, or if you got a hit. Even mediocre shortstops can catch most of the balls they can reach.
Because I am a Blue Jays fan, I hope the Yankees do everything they can to gratify the peanut galleries and keep Jeter out there, day after day after day, at shortstop. I promise you: he will come out of his slump if you give enough at bats.
Blue Jays fans understand the difference a less famous but more talented defensive player can be: Devon White replacing Lloyd Moseby. It was a revelation. I didn't know balls hit into the alleys could be caught.
That said-- please don't come back at me with "well, Jeter's having a pretty good season, isn't he? The adjustment worked." Jeter had a sub-par season last year. Most players who have a sub-par season-- like most teams that have a sub-par season-- will bounce back to some extent. That won't change the essential equation: Jeter's defensive effectiveness is long gone, and .280 with 18 homes runs won't obviate the Yankees' need for a new shortstop.
I would also bet that long-time, faithful Yankee fans will be a little startled when the new kid gets to play. Habituated to Jeter, they will be a bit surprised to see ground balls that they thought were going through snatched up and turned into outs.