it is also the case with let coach decide.
The main diffrence between the 10 players, and those 2 is that those 2 are back-ups.
The coach plays the 10 players, and only in the situations I told before, will he use the back-ups.
the diffrence between the tactical options:
let coach decide: coach will use the 10 players, no matter where you put them in the positions he finds best (I even had my starters mixed up once or twice).
coach picks from dept chart: coach chooses, but tries to keep to the dept chart, he might not follow the chart if there is enough reason for it. Most of the time you will not see diffrence between this and follow dept chart, unless you do unlogic things.
strictly dept chart: coach will only put players where you decide, so he will never put your player that you put in the SG position at SF position, even it is very very lear he would be better for SF at some point. this is ideal for training centers in handling for instance. ;)
dept chart until 4rth: like it says, the coach will follow the positions you order, until the 4rth Q, when he may do as he pleases and the tactics swith to let coach decide.
hope this helps.
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