[EdZ]

So basically radius increases then angular velocity decreases BUT tangential speed increases. This is what Homer meant by Surface Speed. The RPM of the entire system is decreasing as the radius is extended but clubhead speed surface speed increases geometrically as a result of the EXTENSION and not the effort to create more handspeed.

This is why Homer said the Swinger needs a quick start down. As a result of the lever assembly being out-of-line due to wrist cock it is easier to accelerate because its moment of inertia is smaller (think of the string deal with the smaller circle). With a smaller radius you can really get the thing whipping around (accelerating angularly) fast. So you have jacked up the rpms of the system via the out of line condition (shortened radius). Then as the lever assembly gets extented via the uncocking surface speed gets multiplied because the clubhead is further from the center. Thus Homer says the Swinger cranks the gyroscope and then just hangs on. You don't need to "add" you just need to EXTEND. The extension is the mechanical advantage via the conservation of angular momentum. It is LAW. Law don't take no lunch breaks.
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Which brings into question the often mentioned 'straight left arm'.

Indeed, there are multiple consistency benefits of extensor action, but properly understood and utilized, allowing a bent left arm is a power source.