I cannot claim something that is not realistically possible. In order to have such as study it would need to be falsifiable and repeatable. You would have to have the same type of attack, with the same factors, with the same person under the same stress. And it would have to be repeatable. That isn't within the scope of a scientific study.
That was kind of my point. I could certainly design a study to address the issue, but it would be wildly impractical to ever get it done properly in the real world. That's why I take issue when you say that you have scientific research backing up your claim that sparring is counterproductive for developing self-defense skills.
What is (and are referenced in mine and others links) are studies behind the the methodology in which we train. Training used to be simply by rote and nothing else. That instilled bad habits. Since training was changed to a scenario based format, using the totality of what I've described we haven't had any officers killed with an empty gun, full mags and a pocket full of brass. We haven't had any officers disarm someone and then hand the gun back to the bad guy. Call it anecdotal if you like, but it is real world examples that demonstrate one methodology was sub-optimal to the other. Doesn't make the methodology perfect and bad things still happen but mistakes have been learned from.
If you're strictly looking for stats and % then I can offer two off the top of my head. The first is with the Boatman edged weapon defense system. Prior to it being instituted, officers were being injured 86% of the time in edged weapon altercation took place. After implementation it dropped to 17% within two years.
That's all excellent support for the idea that your current training methodology is sound, something that I've never questioned. I'm not sure how it demonstrates that sparring is not useful for developing skills and attributes for self-defense. Was the previous "rote" training which has been improved upon sparring based? If so, how was the sparring conducted? If not, how do your improved results say anything one way or the other about the usefulness of sparring?
Personally, for my women's SD course, no woman I've trained has ever been successfully raped and of those that had an attempt the attempt was defeated. That is a small sampling in the totality of the overall population, but it is personal experience.
How exactly do you determine that none of your former students has ever been raped? Do you conduct annual surveys of every woman who has taken your course to ask "have you been raped this year?" Regarding those students you know of that successfully fended off a rapist - how many incidents are we talking about? 5? 10? 20? 50? How does that compare to the number of LEO use-of-force incidents that you have studied or been involved in?
My point is this:
If you have been personally involved in a large number of violent incidents and it's not required by your profession, then you are failing badly at the most important aspect of self-protection - staying out of trouble. You might be an expert in fighting, but not in actual self-defense.
If you have been personally involved in a large number of violent incidents and it is required by your profession, then you may be an expert in handling violence within the context you professionally deal with - cop, bouncer, soldier, corrections officer, etc - but not necessarily in other contexts. (This is a point Rory Miller has made repeatedly: the world of violence is too big for any person to be expert in it all.)
The conclusion from the previous two facts is that no one can honestly claim to be truly expert in all the aspects of how to train for civilian self-defense the way that a veteran cop can be an expert in taking down a suspect or a veteran boxing coach can be an expert at how to prepare for the ring. The extensive data set just isn't there to draw from. We can take the limited data we do have and extrapolate from the lessons learned in other contexts, but there's always going to be a degree of uncertainty.
Beyond that, I've tried to answer your questions to the best I've understood them and to the best of my ability. That's the best I can offer. I maintain my position because it is what I've seen and experienced and experienced from others. Sport sparring is best for sport, live/street/scenario 'sparring' is best for SD. I've listed the reasons why already so I won't rehash the same thing.
YMMV
In that case I'm wondering if you've actually understood my 3rd question in my 10:46 am post, because I haven't seen anything you've written that answers it one way or the other or even indicates that you even read it. I thought I phrased it clearly, but perhaps I was mistaken. Let me know if I need to clarify what I'm asking.
And just in case I'm going blind and somehow missing the answer - if anyone else can spot where Kong answered my question, please point it out to me or translate if I'm just being too dense to understand.