The system will be the same provided it was learned correctly, no matter what the individual preferences, because of the WSL VT learning process.
I don't double that. My observations are more of a comparison of what I see from other systems and in Wing Chun discussions. Like from a past discussions in here the "split hair" was in regards to how one pivots on the foot as "being the correct way" (I've my memory is correct. I could be confusing 2 different arguments). In other systems how one pivots on the foot isn't a game breaker for correct and being incorrect. I'll use Jow Ga for an example, we do a lot of pushing with the heel down, but the only reason why we stress that is because heel down is the optimum position for generating power and maintaining stability for the types of punches we do. It's the "Best"way to throw that punch and all of the Sifu's will give the student a hard time for not having the heel down. If another Sifu teaches to do the punch down, then it's not the "correct / best" way to do that punch. That one "flaw" in teaching isn't enough to say that one school is "real Jow Ga" and the other school is "fake Jow Ga"
When I read the Wing Chun debates here, and here it from other schools, it seems that the differences are very slight in comparison to the whole system. This debate is so big that it was even highlighted in the IP 3 movie with tyson, where one sifu was from the "real wing chun school" and IP man was accused of having an "inferior" Wing Chun.
And this is the same them that I hear in Wing Chun debates. Aka "My wing chun is better than your wing chun."
I'm not saying that this is what is going on , but that's what it looks like from an outsider looking in. In Jow Ga, there are 2 different schools, one teaches to move back foot first to punch and the other to move front foot first and the old guys will debate about it, but everyone else just looks at both systems as being Jow Ga. One school teaches like this and another school teaches differently. Both schools are correct. My first school taught to move the back foot first to do certain punches, my new school teaches to move the front foot. I used to think the new school was crazy, but after I saw the techniques that followed, it made sense to move the front foot first.
Again as someone outside looking in, it would appear that much of the debate in Wing Chung falls in such a small category that a person would actually have to take wing chun just to know who the lineage is. I'm not saying that there aren't some Bum Wing Chun schools out there that are just wrong from beginning to end, but from the debates that often include, history, lineage, how some sifu who is probably no longer living used to teach, it just seems like if the method was truly "wrong" that someone could show why it's wrong without invoking the Historical God of Wing Chun.
It just seems like a person could just say, "My school doesn't do that technique like that, here's how we use it, and this why the technique is done this way in our school."
Maybe the Wing Chun war will end one day.