Lat Sao (甩手)
The Lat Sao program is something particular to the European branch of the Leung Ting style of teaching WingTsun; the other Wing Chun branches, including the Hong Kong branch of Leung Ting's organization, generally progress in a more traditional manner from the forms to Chi Sao training to sparring. Lat Sao roughly translates as "rolling hands" or "tumbling hands" training.
Lat Sao is a sensitivity drill to obtain specific chi sao reflexive responses. Although it may look combative, it should not be mistaken for sparring or fighting. Lat Sao is a game, in which one partner plays the part of an attacker, and the other a defender. The attacker and defender generally switch roles frequently, or after a set number of attacks. If one is not paying attention, or if the teacher has not explained the drill properly, the training can accelerate and become competitive; if this happens, the students are missing the point of the exercise altogether. Lat Sao is not about hitting your opponent, but about feeding him attacks that he trains to counter. As your partner becomes better, the attacks can be gradually made more difficult to counter by making them faster or more precise. However, once the attack is consistently getting through, it should be slowed down again, so that the defender can identify his mistake, or "hole" in the defense.
Lat Sao can be both beneficial and detrimental when not practiced with awareness of its benefits and its pitfalls. The benefits are generally a more technical and more precise style, because the student spends time testing his limits and finding his mistakes. A secondary benefit is a student's greater confidence and less shock when first confronted with free-sparring programs. The pitfalls are over-reliance on patterns learned in drills and mechanical execution by rote, rather than feeling the opponent's pressure and reacting to it. It is beneficial to confront the students with unexpected solutions to problems posed in Lat Sao, as an exercise and to demonstrate that each Lat Sao drill is just one of very many possible solutions to a given problem. A good exercise is also asking a student to solve Lat Sao problems using newly learned techniques in each program; even if the things they come up with do not work, the habit of investigating the problem from different angles and not taking Lat Sao as something set in stone will help them avoid the pitfalls.
German Lat Sao is being described in the afore mentioned. The German Style Lat Sao in the 1990s and early 2000s was used widely in Europe and America. In German Lat Sao the opponents tend to go through a longer, more complex sequence building it up over time. In Chinese Lat Sao the focus is more on realistic powerful attack, so the sequence generally ends within two-three strikes.
In more advanced Lat Sao the two opponents square off and both try to gain the upper hand, allowing their Chi Sao reactions to take over.