When the off-season rolls around, we typically go to twice-a-week movement training sessions for October through December, usually on off-days from strength training. I prefer to break them up so that we can get more quality work in with our strength training program. Once January 1 rolls around, the volume and intensity of sprinting increases, while the strength training program volume is reduced. It's a big part of our comprehensive approach to baseball development.
One of the reasons there is a bit less movement training than you might see in other strength and conditioning programs is that we do a ton of medicine ball work, particularly during the months of October through January (for our pro guys). Medicine ball drills are great for not only training power, but also because it helps to iron out excessive asymmetries while maintaining pitching and hitting-specific mobility. Our guys may do 240-360 medicine ball throws per week during their highest volume phases.
The fundamental issue with bands is that the resistance is generally so light that guys can quickly develop bad habits – poor humeral head control, lumbar hyperextension, etc. – while doing them. They'd be much more effective if guys would just slow down and use them correctly. Additionally, I'll take cables over bands whenever possible simply because the resistance is heavier and it matches the strength curve for external rotations better.
The overwhelming majority of our guys long toss, and many of them throw weighted baseballs at certain points of the year as well. They pitch less and throw more. They all still get their 2-3 months off from throwing each year, but when they are throwing, they work hard. This is in stark contrast to some of the throwing models I've seen in professional baseball, where many organizations limit players to 90-120 feet with their long tossing, and the only time a baseball is "weighted" is when it gets wet on a rainy day. Guys take so much time off that they never have any time in the off-season to actually develop.