I'm after a little help here. Basically I run my team from the GM role rather than the head coach role as I prefer to leave the head coach to handle all the games. The issue I have is that I like to set the depth chart so players I want to see get minutes are getting those minutes. However, after setting the minutes the head coach completely ignores my suggestions and does his own thing. Is this running as intended and its simply a case that the GM cant decide the depth chart over the head coach? Its frustrating because I find the head coach plays the starting 5 for overly excessive minutes (often into the 40's) and I feel like the results suffer due to players getting overly tired.

It's because you are in GM mode. To set depth Hart minutes use global mode so you can do both

Actually found the issue after I'd posted this. Had the CPU to manage depth chart switched on in the game options. Its doing what I want it to do now.