Joy,
IMHO,
I look at it from a few different angles:
1,
According to the writtern record from Cho family, ( and it is closed to YSK’s )
NG Mui taught Miu Soon in Kui Lin while She travel there.
Miu Soon then create his own version.
Yim Yee, doesnt know what he was taught is the creation of Miu Soon. Yim Yee taught it was White Crane from Ng Mui.
Only before Miu Soon past away, Miu Soon reveal his creation look like White Crane but different.
Later, Bok Lau beg Yim Yee to be his sifu. At that time Yim was quite old, at his sixty and no one knows he is good at kungfu. Yim at this time live in Kui County and open a tofu shop. So, it seems that some how, every one meet at Kui Lin area and SLT was design there probably. Kui Ling has very good scene.
From this, I look at it as, WCK or at that time it was called Siu Lien Tau system according to Miu Soon like to call it. Is a private invention. Joe from the east cost meets bob from San Jose, and bob work for Cisco…and Joe teaches in MIT… stories goes on with doing project in garage… It is not mean for flamboyant showing off. It has nothing todo with killing Qing…
(and ofcause, later when I found out that the emei 12 post has a tradition of ---- can only passed to one monk per generation in the goldern summit temple of Emei. it becomes clear that why Miu Soon keep his mouth shut. Because he is leaking information and breaking the temple tradition — He create something called SLT with his confidential information.
As we know today, there is 9 progessive level of mind/body training in 12 Zhuang which is accord to the stillness or samadhi states.
By the way, the emei 12 zhuang has ground work, not the same as BJJ, but it does go to ground, rolls on ground…ect , It even has hand stand at advance state when one can reverse the qi flow…)
From the history of China, Since the begining of Qing dynasty,
There are 3 generals of Ming converted to Qing King. the 3 kings with thier army reside in the South China. with Fujian and Kwan Xi, Sze Chuan area… namely the Wu San-Kui and Keng Ching-zhong.
In addition, One can today check about the name of the Tong head of the Hung Mun in Kwan Xi, Fujian… in 1800. to observe a part of travelling situation…ect I got the book on this published by the Taiwan Hung Mun association. Bought years ago in book store.
Thus, there is no suprise for the business and travel from Fujian to Sze Chuan..back and forth… for herb, salt,… business…
If NG Mui is Fang Chieh-Niang herself, then there is no suprise she was possible to travel to Kui Lin. If Ng Mui is the third or fourth generation White Crane master after Fang Chieh-Niang, Then, there was no suprise for them to travel in Emperor Chien Long’s era because that is the time China is peace for many decades.
Thus, my conclusion is. SLT is a great art even it has no flamboyant “Hong Kong shaw’s brother movie killing , burning temple, and revenging” . but invented by probably a buddhist cultivator or may be kind of healer or mystic monk today. And, Yim Yee also is not a type of flamboyant people but quitely cultivating his martial art. A conservative type of people.
So, it is an ordinary story which might bored and disappointed some. But, it is a pice of art as piccaso or van goh’s art. A great art is a great art, doesnt matter where it from, palace or village or garage.
Then, the real flamboyat incident comes, that is when the art got to the red boat with all those Opera singer such as Lee Man Mau.
See, Lee is a White Crane practitioner, if I am not wrong, and it makes sense that BOk Lau, Wing Chun ect hang around with those people. Chinese is not very friendly toward other people from other state. Chinese at that time is very tribal-- Fujian is Fujian, Canton… different tribe… But, when they know they are from one school White Crane, that tribal link link them up. Not to mention, the Kuit I have some of them certainly is in Fujian. So, the White Crane connection or White Crane tribal power is in action in Red Boat to a large degree.
People talk about modified WCK, adapting WCK, marketing WCK. Honestly, I dont see a problem. See, Miu Soon is modifying his White Crane or Emei 12 Zhuang right? Those in the red boat opera is Marketing their art too right? otherwise how come we have so many great stories? and now we get screw with some of them. 
If we cannot accept the modification, adapting, markerting… then we are hypocrates because the ancestors were doing it.
The rule of physical world is grow or vanished. I believe Miu Soon knows more than me about Spiritual and physical grow, otherwise he will not be thought the 12 zhuang. That shows he was some body high position related to the temple.
Now, people might then question why the heck is Hendrik constantly annoyingly bring up root , root , root… Honestly, I am not looking for ORIGINAL. because ORIGINAL doesnt exist. Ask Miu Soon what is ORIGINAL? Ask Those from the Red Boat what is ORIGINAL means? Ask Yik Kam what is ORIGINAL? Now, my concern is ----- without a proper in dept understanding of what SLT do and is capable of. We dont know what is it, what is it’s limitation, what is its capabilities. We want to find out WHAT IS SLT.
I arque big time with some GM of other Style about SLT is not equavalent. Why? For myself , I careless about those. Anyone can claim anything, one can train SLT similar to Iron wire or Shao Lin or… anything, it is a free world.
What I care is if the root being Screw up. Who are we? If we can’t even sustain an inrush … how can that be WCK as describe " great in neutralized incoming force, neutralization and attack in the same instant?" One want to contiously widern one’s stance to take the inrush power? because one see no way in the YJKYM? If SLT has become a useless riture then might as well get rid of it.
Ofcause people can think anyway they choose. But, as a WCner, Not a GM, I believe we have responsibility to tell the truth. everyone, anyone. Is it or is it not. Not to say or fantasying WCK is omni super…
Nothing in the world is perfect. If WCK can do something, we better say it. If WCK cannot do something and it is in the edge of losing it. We better say it. Or else WCK dry up and die.
Who is perfect? But, I believe everyone, every lineage has a pice of good thing, we all can treasure.
Say even HFY who some might think I am always argueing… ect, I think it is great that they create fomulars, flow chart, good for the starters to learn with more structure teaching like TKD…
There is no suprise some loves it because it is structure and clear. That is the good part. good for grow. See.
But, Fomulars flow charts way have limitations, it cannot lead into the advance art.
There is a saying, “if you copy me your art die.” In Chinese martial art circle on how sifu warn thier students. Check it out.
Not to mention in Chan — Mind is only a part of reality; and how is one grasp that reality if one doesnt attain that state. Formular doesnt work, Space and time doesnt work there because time, space,… is within the mind, and mind is only a part of reality Not all. Chan is everything but not attach to anything. attaching to method is called Dharma attachment. attaching to self is called self attachment. Chan has to break this two attachment.
Dont believe me? ask oneself, can one plan everything one will do from morning to night like a robot for tomorrow? including which car one will see in the high way…ect. But we can see yesterday clealy and precisely. right? But we cant live in yesterday which we know it all. we can only live in the now where we dont know it all, but live.
That is the paradigm of non dual. There is no concern of enlightement or not because one live in Non-dual.
It is not about getting enligtement. It is about not dragging on yesterday, dragging on what has been done which cannot be changed and cannot be live in the same condition again. It is not about fantasying tomorrow Diaz will visit me. live NOW.
Go live and learn with some great masters in art or spiritual , and see if they go with structure or they are so un organized non structure, keeping changing…
but there is something within thier work within them. Those are their styles…thier way .. their Dao… Until one has one’s own style within, how can one called oneself GM?
Get real living in NOW or else we all are living in idealistic fantay.
Can I be wrong? Sure, take what can make you grow and left those what I am wrong about. I am just human, it will be great if I can be right 60%. Just 60% and I am happy. because my mind is only a part of reality right? 
Just Some very wacky thought.