Muscles don't push. I'm not really trying to get into sequence stuff, I'm just explaining how the rotation happens since I don't think it has ever been explained in this manner. A lot of people know the criticality of coil, staying back (to not lose coil), launching rearward, etc because this leads to good execution, but at a fundamental level, I don't think many people understood how it worked.What muscles fire first. Glute pushing or obliques pulling? same time?
The key to the high level swing is the interaction between rear hip coil and the firing of the glutes. Without the coil, the glutes will just thrust the hips (no rotation) therefore the rotational element, which is required to get the bat into the zone, will need to come from other sources like spinal (shoulders), core torque (hips), front leg pushback (push-block), etc.
Hopefully this knowledge will shift people's thinking and lead to some changes in how the swing is taught.