In JA2, the way that trainers and students work is a bit lopsided. Mercs become tired at different speeds, and require different amounts of sleep. Therefore, when training, it is not rare for a trainer to be asleep while his trainee is getting tired, and so they keep switching around (one's asleep while the other's awake). If players want to make the trainer and student work at the same time (and thus earn the bonus involved), we need to micromanage their sleeping hours. This can get tedious very fast and is much harder when training a large group of mercs simultaneously.
The Smart Training Handler takes care of this problem by synchronizing the sleeping hours of all trainers and students so that they go to sleep and wake up at the same times.
While this may be a minor feature, it's quite a complex one, as it has lots of different INI settings - but you'll probably want to keep the default settings anyway. With the system fully turned on, if a trainer goes to sleep then all his students will go to sleep as well. Also, if all students go to sleep, the trainer will also go to sleep. It works the same with the wake-up times.There's also a nice new setting that will control what a student/trainer does if they wake up and no one's available to work with them. Instead of training on their own (without the trainer, who's sleeping), they'll actually rest and wait until the trainer wakes up. The same occurs if the trainer wakes up and finds that all his students are still sleeping (although he should automatically wake them all up, if the system is fully activated). Please note that if students rest, they don't study, so in a trainer/student combo you can ONLY gain experience when both characters are awake!
The effect of the fully activated system is an increase of roughly 10%-20% in the efficiency of training. You won't have to micromanage your character's sleep times. Additionally, the player won't need a second trainer to cover the "dead hours" when the main trainer is asleep. On the other hand, the trainer's characteristics are much more important now, as his sleep/fatigue values will affect the training speed of the whole group - so characters who get tired quickly and/or have to sleep alot are less efficient trainers!
Also note that with the system fully turned on, sending a trainer to bed will send all students to bed automatically, and sending all students to bed will send the trainer to bed automatically. This will keep the synchronization. If a player wanted the trainer to sleep alone, the player would have to change the mercenary's assignment first.