When it comes to actually being in the box hitting, you cannot think about anything other than seeing the ball and swinging. 100% concentration on the pitch.
The grandpas in the stands yelling at little Timmy to keep his elbow up make it almost impossible to hit when they encourage a kid to think about mechanics during an at bat.
Mechanics should be worked on during tee/front toss/BP. But when it's game time you should only be concerned with seeing the ball.
FTR, I like your WIN approach.