Unless you have a natural tendency to hit the opposite way from either side, like a Boggs, maybe Beni or Moreland on occasion, it is a very difficult thing to do and almost impossible on any pitch middle in. To microtime and adjust your swing precisely, away from the tendency to swing hard, pulling the ball with your body momentum is a true skill for a mature hitter. Xander has shown good bat control going to right often, and Vaz seems to be able to execute a part of the time. The real success comes when the hitter realizes the ball is on the outer half and can drag his hands through the zone slightly behind the ball. That sometimes happens when the swing is late anyway.
IMO, Jackie does not yet have the plate discipline, pitch recognition and overall skills to consistently poke the ball up , up and away or on the ground to the left side. If he did, and made defenses play him straight away, one extra hit per week over the season would be worth a lot. 125 hits in 600AB's is .208BA, add 1 hit per week and it magically becomes .252 . The OPS should certainly rise as well as some of the 26 hits will be extra bases. If JBJr is expecting to get a decent FA contract, the best thing he could do is hit oppo and make the defense honest.