There probably is no better example for how much Wing Tsun can be learned in 3 years than these kids from Armenia. Just take a look at this 15 year-old girl's chi sau skills:
Or this 17 year-old who knows bart cham dao - the highest skill level of Wing Tsun:
Okay, so maybe he isn't Leung Ting yet, but pretty damn good for three years of WT, wouldn't you think?
Guess who his father's (who taught him) teacher is? Go figure it out yourself. It's all right there if you look for it - and then consider how your own Wing Tsun career could have gone if he had taught you the way he taught this boy's father.
So, all of Wing Tsun in 3 years? Why not?