Chris, muscles themselves are not modeled, only the fact that they produce an active torque and an associated reaction torque on two adjacent segments. Muscles do need some state of minimum tension to maintain structure and to be able to swing the golf club. Total relaxation is not quite possible, afterall a golf swing is a rather strenuous activity. Better to think in terms of a relaxed state of alertness. A cat-like readiness.
Following Mindy’s ideas about relaxed muscles producing optimum power one could reasonable expect this to translate into quite large clubhead speed and corresponding ball carry. However, Mindy Blake, Snakedoc and Richard are only obtaining quite modest carry. Proof is in the pudding.
The idea of having no torque applied between the active inner pivot and the hands follows the same logic as in Gravity Golf - any active force sets up an associated counter force and hence inefficient. Applying only torque at the inner pivot and keeping all muscles between this pivot and the hands passive prevents this to happen.
This last argument looks very convincing on the surface but needs a bit more consideration. We can apply a torque at the wrists and at the shoulders. Wrists should be either passive or apply some retaining torque. A positive wrist torque from the top of backswing is indeed counterproductive and only moderately useful later in the down swing.
Torque between arms and shoulders is a perhaps a matter of style/preference. You can sling totally passive arms with the body or torque/drive the lead arm/trail arm claw during the downswing in conjunction with an active ‘body’ rotation. Difficult to tell what is optimum for any particular golfer.
It always intrigues me that almost with anything I try the measured clubhead speed does not vary much. This might be with extremes such as a Gravity Golf swing or a very short tight muscle controlled swing, it does not seem to matter.
The body is a very complicated machine and can be used in various ways to produce clubhead speed. It is quite reasonable to assume that for a particular golfer a rather inefficient swing can still, for him, produce near optimum and consistent impact conditions.
I feel that at the level of the average amateur the important feature is to have a golf swing which allows foremost correct impact conditions to occur and to be able to repeat it consistently. It is here where Mindy’s swing is quite interesting - simple swing motions, very elongated trajectory through impact, no rotation of the clubhead, etc.