NCUlEFT,quote:
“people say sometimes my arm drags...what exactly does that mean and how do you fix it? Does it have anything to do with flying open?”
This poor mechanic is a shoulder injury at many points waiting to happen, first Humeral miss alignment at initial forward force causes posterior labrum fraying, anterior deltoid, 2 types of cuff muscle tears and capsule ligament loosenings.
It is caused solely by not physically locking in alignment at the right time from not being aware of this static contraction mechanic.
The fix,When you pendulum swing your ball arm straight back with the thumb up, it will allow you to then transition early correctly by outwardly turning your (inside of Elbow up) humerus. Right at this point is where you lock your humerus (upper arm) in line with your acromial line (shoulders), right when you start initial forward force application and all the way through to release and after during deceleration your humerus should not angle itself as much across the front of your body because now you have attained more shoulder rotation also that looks like “flying open” to traditional pitching coaches and knowledgeable observers. This more fuller rotation is a good thing if the humerus and shoulders line up during drive.