I think it is important to note that the whole hardpoint vice cable handle/ vertical vice biased grips/skinny solids vice fatter cables/upright vice palm up or down (and I'm sure there are more) discussion is driven by the way the consistently high finishing in major competition, top level fliers have refined their equipment in the PAMPA/internet era; combined with the desire of fliers hoping to displace these guys to refine their patterns to do so.
I've lived through the vast majority of stunt history--either as an avid young learner or as a committed competitor--and think I can say, without fear of contradiction, that the ability of fliers to share their own experiences, experiments, triumphs and failures with the rest of our small fraternity of fliers has reached proportions that were unthinkable when I first started flying. The ability to do so and the interest it attracts has allowed us to work our way through the big stuff that allows almost anyone to reach the local Expert level and all the way down the list of less obvious but still important things (power trains, flight trim [CG, tail size, aspect ratios and any number of primarily aerodynamic factors that influence the quality of our tricks) and now, having pretty much filled the library in those regards a have worked our way to the other end of the lines where the mechanics meet the manipulator.
When combined with the willingness of the very best of us, Paul, Brett, Bobby Who, Igor and any number of others to share what they've learned that help them become household words in stunt homes we now enjoy the distinct pleasure of being able to discuss the minutiae of things that take one from local expert to National or World Championship levels. There is literally no aspect of stunt flying that hasn't been learned, shared, debated, debunked and/or certified as gospel through the products and universal resources provided by the hard work of guys like four decades of Stunt News Editors, Sparky and the Newmanns.
So, first of all, a big thank you to those who have made the resources available to do so. Wouldn't hurt to throw a few names into the discussion, by the way.
The level of discussion that has resulted from the debate started back in the mid '90s or so about the control handle/human handler has been, almost unique, with respect to its continued interest and ability to generate differing opinions and advocacy. Yup, We've had the schnerle wars; the tuned pipe wars; the four stroke advocacy era, the contentious ARF debate, the struggle for acceptance of (yuch!) Faraday based powerplants; all of which were vigorously debated but in a comparatively short time selected winners and losers and became either universally accepted or matters of personal choice and more or less disappeared from the forums and pages of the press (albeit Bubba Hunt keeps the bugles blowing pretty consistently for the coil and magnet crowd although the votes have pretty much been tallied). Yet, here we are 20 years into the discussion of the most basic aspect of our endeavors still discussing the interface between the human and his machine. I think that is fascinating! I haven't done it but I would guess a search of threads on Stuka Stunt and Stunthangar would uncover several dozen different threads on the subject of handles, in particular the emergence of hard point types as a viable if not superior alternative to the previously superior and ubiquitous Baron style adjustable cable type. Second would be the number addressing preferences for and arguments pro and con re vertical grip versus the "natural or pistol" grip versions.
Now, just when you think the thing has been beat to death the current subject, the potential for mechanically induced errors to patterns based on how the handle is held in the pilots hand while doing the tricks. Awesome!
That our discussions have resolved the puzzles down to this degree of fine tuning can only be a good thing. Read it all and enjoy the fact that we all can.