In the old days, martial arts training was quite brutal. One had to listen and do as one's sifu asked.
In teaching the student to use juen-ma (turning horse), the sifu would get the student to practice on top of a high table. The idea of this training is quite obvious -- if one used stepping as opposed to turning, one would fall off the table! So, this was a sadistic way to 'force' the student to turn \ swivel instead of stepping backwards, which is the most natrual tendency.
I personally think this type of training has benefits, but it really doesn't suite a society filled with spoilt brats. The parents would be taking the teachers to court for abusing their children.
However, this concept still may work if practiced on a slightly raised platform, but obviously this doesn't have the same effect as a tall table top.
This type of practice probably dates back more than 1000 years' in Chinese martial arts, but it's difficult to place an exact time. In regards to wing chun, it probably dates back no more than 400 years' since that's roughly the age of wing chun.