Different Wing Chun lineages follow different steps in the sequence of developing chi sau. The chi sau of Yuen Kay San and Koo Lo Pin Sun Wing Chun, for example, follow a different set of steps to that of Yip Man Wing Chun. Yip Man Wing Chun has no wrist rolling chi sau whilst Yuen Kay San and Koo Lo Pin Sun Wing Chun don't do the same dan chi sau as the Hong Kong version. Chi sau, however, is the quintessential Wing Chun exercise, occurring in some form in every Wing Chun lineage. Everyone who has heard of Wing Chun likely knows that it is synonymous with chi sau. In fact, it is one of its distinctive features. So many Wing Chun practitioners invest so much time and effort into it. In fact, it has become an obsession with many who spend most of their training time engaging in it! Some gwoon seem to even only train forms and chi sau!
Chi sau is often much misunderstood and, in my experience, is often neither systematically nor comprehensively taught in many gwoons. On the other hand, in some gwoons and organisations it is taught very systematically and logically. (Albeit that some have divided up Wing Chun learning, including chi sau, into innumerable money-spinning grade levels!). In others, some of their standard drills are quite bluntly utterly bizarre and amount simply to “chasing hands”. Others resemble a bizarre cadenced dance routine with instructors even counting out the beat! These must fill up time-consuming grade levels, I guess! In yet other gwoons, the practitioners shamble around in some sort of stance which doesn't resemble any respectable Wing Chun stance and wrestle and lean their way through their chi sau, looking like they are engaging in a Frankensteinish version of Mongolian wrestling! In all too many otherwise reasonable gwoons the practitioner is simply left to figure things out for themselves without explicit instruction. I refer to this as the “caught rather than taught approach”.
Then, of course this catalogue would be incomplete if mention were not made of those who ought to know better but still repeat the patently false mantra that being skilled at chi sau in itself automatically means being a skilled fighter! A moment's reflection will reveal how illogical such an equation has to be. Real fighting involves a number of variables which distinguish it from the collaborative partner exercise of chi sau. Whilst chi sau is a useful exercise it is but one of a number of drilled and developed skills and attributes necessary for skill in fighting. There are a number of other drills at least equally important.
Going too far in the reverse direction is an error too. I laughingly once heard it said, that everything the practitioner does in chi sau is not applicable in actual combat. It is - if you do correct chi sau and know how to apply sticking in real world fighting! In genuine Wing Chun nothing is trained which is not directly combat applicable whilst adhering to the governing principles of the Wing Chun paradigm - nothing! It is simply a question of knowing how chi sau drills are applicable to real combat. (And, of course, it almost goes without saying - actually having the execution of the technique correct and actually knowing its application to start with).
Being able to understand and exhibit the key skill of sticking (one of the key words of the Yuen Kay San system) in a real fight logically involves both chi sau and san sau practice. Further, it involves a comprehensive rather than a minimalist and a controlled rather than a random approach to chi sau. All of the Wing Chun techniques learnt in the forms need to be progressively and systematically drilled in combat realistic fashion first against cooperative and then against uncooperative partners in both chi sau and san sau. The same applies to the technical expression of all of the key words (biu, chi, chit, chum, darp, dong, jeet, lao, mo, tao, tong, tun).
Chi sau in essence teaches and engrains into the neuro-muscular system the Wing Chun mindset of accepting and sticking with the attack, staying with the attacking limb as it returns and striking along an open path when the hand is free. It simply teaches the practitioner to be able to control the attacker once contact has been made and to flow with their movement until they are shut down and rendered immobile and incapable of movement and, logically, further attack. Whilst it can, and ought to, be enjoyable, chi sau is not simply a game-like routine gwoon activity the practitioner becomes skilled at in isolation from being able to apply the skills learnt against an attacker who isn't fighting within the Wing Chun paradigm and has no idea of the chi sau routines - the non- Wing Chun fighter attacking from the non-contact position. In short, chi sau doesn't exist in isolation from its application to the real world.
Chi sau drills ought to teach the Wing Chun practitioner to take advantage of weaknesses in a partner's structures and dynamic control of their arm contact and pressure. Chi sau also teaches the practitioner how to initiate breaking structure and/or the partner's contact and causing the partner to exert inappropriate and thereby self defeating pressure. Hence, chi sau drills teach both how to react to, and how to initiate attack. Chi sau, properly taught, also teaches attributes and skills like being comfortable in close range fighting; simultaneously turning attack to defence; closing off one's centerline; peripheral visual monitoring; controlling balance - one's own and one's opponent's; relaxation; speed; reactivity to the opponent's pre-strike and/or striking tension and/or movement upward, downward, rotating, laterally or forward; an appreciation of correct structure; forward springy force; not telegraphing one's own attacks; an appreciation of line; taking advantage of inappropriate structures; and, bilateral coordination. Unfortunately, it also necessarily teaches these against another Wing Chun practitioner - who will react very differently to most attackers who are by far generally non-Wing Chun fighters.
To be skilled at the attribute of sticking in real fighting, versus being skilled at whatever drills the practitioner's gwoon engages in, the Wing Chun practitioner has to be able to exhibit the skill of sticking with the attacking limb of the opponent whose arms will definitely not be held in the tan, bong or fook sau positions. The Wing Chun practitioner has to be skilled at meeting, controlling and sticking with the opponent's bridges under any circumstances.
Hence the question that ought to be posed to the Wing Chun practitioner is not: “How good are you at chi sau?” Many folk mistakenly believe that if they visit practitioners from other gwoons that if they engage in chi sau this will indicate who is the better fighter. It may. But most often it simply indicates who has better knowledge and understanding of, and experience in, chi sau per se. The question which is most appropriate is rather: “How good are you at applying the concept of sticking in a real fight to an uncooperative non-Wing Chun fighter?” Being skilled at chi sau does not automatically translate into being good at realworld fighting or being able to stick to an opponent in such a real fight - despite what many may've been told and unquestioningly believed and repeated. Within the Wing Chun way of thinking it ought not be the fame of the person saying anything which automatically makes it unquestionable - it ought to be systematically applied and informed logic which determines its correctness.