What I have noticed is that the game changes general settings in the background while switching between my MyCareer and MyGM like Auto-Defense/Offense or the Position lock. Maybe it tweaks the tendencies by itself, too, because I exactly see the same thing in my MyCareer with less movement after switching back from MyGM. The first few games it seems like I have to do everything on offense and my teammates don't shoot open 3s or refuse to cut to the rim which makes my team lose a lot. It's stupid, weird and annoying.