When shooting fast and aggressively, elbows are slightly bent and I'm bent forward in a boxer's stance.
When shooting for accuracy, I'm a bit more erect, and elbows are a bit more bent.
Either way, I'm squared up to the target and do NOT do the push/pull thing. There's no such thing as "locking the gun in place", IMO. It's a futile endeavor. A neutral grip, in contrast, keeps the muzzle returning to the same place each time, which is a more effective way to manage the muzzle.