There is no inconsistency between the man's LH to lady's RH hold forming part of the dance frame, and the hand-clasp NOT being used in guiding or leading.
The joined hands move, as the couple move, but the relative position of the hands (and therefore the frame) remain static, and do not alter from moment to moment.
The fact that the muscles of the dancers' bodies are braced at all times means that they will feel the rotation of one another's bodies, but the hand-clasp is the least appropriate point of physical contact from which to 'communicate' the intention to rotate. Men do not 'steer' their partners around the floor using the extended arm as though a tiller on a boat, but rather, the couple move together, the lead having been already felt elsewhere.
The fact that in rotation, the movement is most apparent at the extremity of the frame (the point farthest from the centre of rotation) emphatically does NOT mean that it originated there.