[6bmike]

As a swinger, this point always seems to throw me; what differentiates this sensation from hitting? It does feel (to me, at least) like my right arm is driving; without this sensation, my right arm collapses.

The right arm is always driving to become straight. This might be what you feel.
The difference is that a Hitter drives an angle directly to the ball...
and a Swinger cranks his gyro- right shoulder- to "ignite” the blast off of the left arm, the fourth accumulator and whirls the clubhead. This arc of approach “freewheels” (a non tgm term) the Flying Wedges. Since the right half of the wedge extends to the right arm, you will feel it- it just can’t muscle and push the shaft near impact. Trust Newton and let the head whirl.

back to the egg.