2018 works with a Cressey trained guy as well.
COACHLD, I haven't seen anybody say upper body strength is a bad thing for a baseball player. It's a key part of overall strength and conditioning for a ball player. A few people have suggested using caution with the trainer your kid is signed up with. Is the trainer dialed into baseball functional strength and workout protocols. Some upper body strength moves (military press ?) aren't necessarily appropriate for an overhead athlete. Cressey has really increased awareness levels for athletes, the athlete parents, as well as trainers. As long as we're all educating ourselves and passing on good information.
My boys have attended a well funded HS program, but the HS strength and conditioning coach is a know it all and his workout programs are tailored to football guys, he wasn't even receptive to an adjustment to the upper body strength program which might be applicable to baseball guys. This guy totally screwed up one of our star baseball players a few years ago, went too heavy on the upper back and chest, lacked symmetry with his muscular development, reduced the players throwing movement, the player looked liked a short arm shot put guy. Helped the kid win state in wrestling so not the end for him, but this scenario really opened up the eyes of all involved in baseball. All of sudden everybody knew who Cressey was...
Gov is spot on. Our well funded HS has awesome facilities but turn key workouts that are driven by football strength and conditioning staff. My son goes to these workouts but doesn't do the football focused portions and does his Cressey program.