It is interesting to me that people have an abiding interest in “Tongs” and Chinese martial arts; there is a fascination about it that far exceeds any reality to it. As a prosecutor and public defender who has worked both in the California and Taiwanese criminal justice system I would point out a couple of things.

First, most gangsters, be they Californian or Taiwanese, have no great interest in learning or practicing any kind of martial arts. If gangsters are going to attack someone they rely on:
Surprise
Outnumbering the victim/opponent
Using a club, knife or gun

Gangsters do not rely on some in depth knowledge of martial arts. In fact stabbing or shooting someone to death is quite easy and requires no training whatsoever. It simply requires the willingness to do it and getting the victim by surprise or by superior numbers.

Gangsters generally like their whiskey and their women and tend not to be the kind of guys who bother with learning martial arts. To the extent they know how to fight that knowledge came from on the job training. And they see no reason for formal martial arts, most gangsters have a fair amount of contempt for organized martial arts.

The upshot being, I doubt seriously if gangsters ever really had much to do with Chinese martial arts. The village arts of southern China were developed either as temple entertainment or for use in village militia (yes, I meant temple entertainment---a type of folk dance performance). In any event they had, at least based on the historical documents I have seen (which are few and far between by the way), nothing to do with gangsters.

The problem you get, and you see it quite a bit in Taiwan, is that there is kind of a gangster chic. Everyone wants to hint or kind of claim that they know some gangster and that that gangster is a dangerous dude who knows some obscure form of martial art. It just does not jibe with the reality of things.

Take care,
Brian