One reason I'm curious about this is that swing weight, as measured, isn't a frame's true "swing weight". You can have two frames of equal swing weight but different static weights and the heavier of the two will be harder to swing for obvious reasons (swing weight is measured from a point on the handle but we swing from our core and shoulder).
The reference swingweight measured at 10cm from the butt end is the true swingweight, it's just not the only swingweight. This location was chosen long ago as being the place where the thumb and forefinger meet, which is typically the axis of rotation of a person's grip. You're right, though, that it is possible and perhaps useful to consider swingweights at other axes of rotation, such as at the wrist, the elbow, the shoulder....beyond that I'm not sure.
But keep in mind that studies done on golfers, baseball batters and tennis players have shown that there is a linear relationship between the swingweight at the wrist axis (which necessarily includes the weight of the hand) and maximum swingspeed. It turns out that the effective swingweight at the wrist axis is more or less proportional to the the 10cm reference swingweight.
These studies have shown that static mass does not correlate with max swingspeed. So if you have two racquets, both with 320 swingweight but one being 340 grams and the other 320 grams, a player will be able to swing them at approximately the same speed. All things being equal, a more headlight balance and/or lower static mass will reduce the wrist-axis swingweight a little bit, but it's not a big deal. (For example, two frames weighing 340 grams, both with 320 swingweight, but one with 31cm balance and the other 32cm balance - the more headlight one will have a wrist-axis swingweight that will feel more like a 315 swingweight frame. But this one will swing quite different, in terms of "swing feel" and timing, and even though it may be physically easier to swing you may not care for the way it comes through the hitting zone.)
It would make intuitive sense that the effective swingweight at the shoulder joint axis would limit swingspeed, however, especially for the serve. Higher static mass and/or less headlight balance will increase the effective swingweight at the shoulder, if the reference swingweight is kept constant. But the relationship between the shoulder axis swingweight and maximum swingspeed on serve has not been studied, to my knowledge anyway. This remains mysterious territory.
The poster/salesman Stoneage provided us all with a spreadsheet to calculate the effective swingweight at various axes in a thread from last year. (Although he converted effective swingweight into "equivalent mass" for some reason.) A search will turn it up.
In experiments with frames matched at a base set of specs I've noticed that frames with higher static weight feel more stable but at some point that extra mass gets so hard to move it inhibits racquet head speed and therefore spin and even power at some point, especially on volley.
On the other hand, a lower static weight frame with a high swing weight can feel almost too powerful since you can sometimes generate too much RHS and therefore power.
I disagree with this strongly. There is no such thing, in my view, as too much racquet-head speed, or too much "power." I think what you are actually describing is a lack of control, not an excess of power. Consider the pros: they use racquets that have much higher swingweights, and are therefore much more inherently powerful, than what we use; they also swing these powerful clubs much faster than us, and yet they use strings and string tensions similar to what we use. They swing faster than us, with more powerful equipment, and they are the best in the world.
The physicist Rod Cross made some great observations some years ago about the benefits of a heavy handle to control in this article:
http://www.racquetsportsindustry.com/articles/2006/04/racquet_handle_weighting_and_m.html
More recently, the poster travlerajm proposed a double pendulum model to predict the effect of various weight distributions on the timing of groundstroke swings. "MgR/I" is the search term. A very useful formula in my experience, although it has its critics.
For any given player there seems to be a sweet spot that really isn't captured with current paper specs. It depends on physique, strength, arm length, height, etc. And therefore it seems almost impossible to say that player A prefer a static weight of X without ALSO specifying a SW at that given static weight.
Many players have made the same observations and mused along similar lines. There are a lot of threads on this topic from the past five years or so. And I disagree that that "sweet spot" you're looking for isn't captured with current paper specs. It's right there: swingweight + static weight + balance.
