I'm also curious about the exact effects of development budget and good coaching. Without having done any studies I've noticed maxing out the development budget to $24m seemed to make a pretty big difference. You have to figure its worth it, even if its as minor as a 5 percent positive nudge in development, that bonus is being spread across every level of your farm system. If you're playing with the standard MLB setup some teams have 8 levels of minors + an international complex. Thats 225 + players being effected.
A simple, albeit time consuming test I may run:
Make a 24 team fictional league with 4 levels of minors (no opening draft). Takeover a team with midlevel farm system. Turn off coaching (i'm assuming this sets all coaching attributes to neutral and average).
Backup and sim the same season 10 times with player development set to $6m. Then do the same with it set to $12m, and then again with $24m. Log the farm system ranking after every sim.
Then do the same with minor league coaches. 1 sim with their attributes set to 100, one with attributes at 50, and another with main attributes set to 200. On this test you keep youth development at baseline $12m.
I think i'm going to do this or Markus could just tell us what the exact effect is and save me the trouble
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