Your ignorance of Kung Fu is a beacon for the masses. To ignore. Idiot.
And your misrepresentation of the facts is even more stupendous. I wrote:
In short, professionals who make their living putting themselves into hostile close quarters combat situations do not prefer or usually even speak of Kung Fu (regardless of the style).
In a miserably unsuccessful attempt to refute that, you manage to cite, nothing that refutes "professionals who make their living putting themselves into hostile close quarters combat situations do not
prefer or
usually even speak of Kung Fu (regardless of the style)." (i.e. law enforcement, corrections officers, and special forces). Instead, you cite
only one of many martial arts instructors who teach at the USMC Martial Arts Training School (USMC-MATS), someone who happens to have a WT background. Christopher Collins also has a kickboxing background, among a couple other disciplines.
Here's where you become educated. The United States Marine Corps literally has it own martial art called the Marine Corps Martial Arts. This formal program is taught by many different USMC certified instructors as part of The Marine Corps Martial Art Program (MCMAP). It has evolved over decades, heavily derived from not only the Okinawan Shorin Ryu Karate by which early proponents of MA-based USMC combative training were influenced, but also fencing, kickboxing, Judo, and Jujitsu, and real-world lessons in battle.
You will find a number of USMC certified MCMAP instructors who have backgrounds in a range of arts, teaching various levels of MCMAP at the USMC-MATS. That doesn't mean they're teaching "their" arts to the Marine Corps. If they're a USMC-MCMAP instructor, you can bet your ass they're teaching MCMAP, with a little of their own interpretation tossed-in, of course.
Chris Collins serves in the USMC as a member of Force Recon. An impressive accomplishment, to be sure. While Collins was active duty, he "taught" hand-to-hand combat to his Marine peers. That doesn't make him a USMC hand-to-hand instructor nor does it mean Collins was "teaching WT to The Marines". He may have taught WT to "some Marines", but that is different from claiming he 'taught WT to the Marines' as part of some official USMC program.
You often find people who enter the military with a high degree of training in some martial art and they will become known among their peers as the 'martial arts guy'. Contrary to what some may believe, most law enforcement, corrections officers, military and special forces members possess very little or no formal instruction (MA or otherwise) prior to entering their professional training.
Most of their peers aren't going to know Wing Tsun from Wing Dings, they just want to learn a little of [whatever the resident martial arts guy is willing to teach them] to complement their 'official' military hand-to-hand training, which many law enforcement and special forces members feel to be 'rushed'. This training is usually done on their own time, not under the 'auspices' of the US Military.
In fact, there is a real problem in the martial arts community with people making false or misleading statements for marketing purposes, claiming or strongly implying that they were 'authorized' to teach [insert martial art here] to the US [insert military branch here], when in fact the true nature of any 'instruction' was exactly as I described above.
If I worked at Walmart, and taught some of my Walmart co-workers a little hand-to-hand, that would not make me an "Official Walmart Hand-to-Hand Combat Instructor." It means I taught hand-to-hand combat to some of my Walmart peers - nothing more.
What you have found is an exception in the law enforcement, military, and special forces community, but then again, it might not be an exception in that Collins may not be 'teaching WT to Marines'. More likely, he's teaching standardized USMC MCMAP, with his own interpretation tossed-in based on his extensive fighting and combative experience (which is not limited to WT).
Oh, yes, on edit: And I'm sure Chris Collins could kick my ass using nothing but purist WT techniques and one hand tied behind his back. At least, I hope he could. He's a member of an elite commando unit legendary for its toughness, has been a highly-proficient practitioner of [various] martial arts for years, and has fought in dozens of high-level competitions, including kickboxing.
That is not the point.