Why we cannot get a clear names of Wing Chun movements.
I will do my best to explain this in my view of Teaching, learning and understanding Wing Chun.
The "transliteration", or how the names are spelled using Roman letters i.e. A, B, C - doesn't matter since they're all written the same in Chinese itself.
The different spelling is a result of dialect, accent, and history. People, usually Westerners, wrote what they heard i.e. Peking instead of Beijing. And what they heard differed based on what part of China their sifu came from.
Even up to 50 years ago there was no accepted "transliteration" from Chinese into Roman letters - Romanization. Today, however, Pinyin is the standard accepted transliteration method used.
Yet a problem still exists for many Westerners. Pinyin is used to transliterate the standard Mandarin dialect - known as PuTongHua. In the West, Kung Fu words didn't come from Mandarin speakers. Rather they came from other dialects such as Cantonese, Fujianese, and others.
So if you get confused by all the different spellings and pronunciations and want to get it straight … all you have to do is learn to read Chinese or better yet learn calligraphy)
Remember that much like the system of Wing Chun the Chinese written language uses Characters, the meaning of the character can change with a slight but simple stroke intended or not.
The names may sound the same, but how they’re executed, such as the angle, direction and complete movement will change the meaning of a familuar block, strike, kick etc. Example, Jum sau In Sil Lum tao it is simple to see and be done, but as you advance to more complex movements and combinations, what looks like Jum sau now is called something else. Why? you may ask well......this is where it all gets a bit sticky (no pun intended) from my research, alot of it is a mix of dilect differences, how the movement is done, and above all the idea behind the movement. Idea you ask?, meaning.... that what we call Tan sau for example is only an idea of the movement none specific to a certain strike. Another example of this would be a Tae kwon do outer forarm block, what does this tell you? automatically you think the block is used for an out side attack with the forarm, now to cover an inside attack another name has to be given inner forarm block once again depicting that you must use a different tool for a strike to a different area the list goes on, in contrast sticking with Tan sau this cover (in my Linage of Wing Chun we call it a cover not a block) covers both areas but is not limited, the tool of Tan sau can be used in many ways without using different names. Whats the idea behind it? it all goes back to Wing Chun principles, concepts and ideas.
This does not mean that the blocks of Tae Kwon Do or other arts using this method cannot be used for something other than it's name, but in my opinion it limits thought process and cognative expansion.