Bassai Dai Bunkai - a data/evidence based approach:

Given moves in kata have more than one bunkai (stated by a number of masters of karate in the early 1900s; reviewed  in "Seienchin"  ISBN 978-1-4092-3733-4, pages 11-13), a variety of Network instructors have been fine tuning kata bunkai selection by pulling from the traditional pool of karate techniques and overlapping that with at least the following:

• street fighting data 

• emergency department data from street fights

• a technical audit of 50 UFC fights

• interviews with BJJ/Judo experts

An evidenced based analysis (driven by data) allows one to create at least the following  4 categories of violence which may be relevant to karate-ka. Depending on the need of the practitioner, or emphasis of a given dojo, one may select a bunkai set for Bassai dai, or any kata, that matches the below (rather than simply following classical martial arts or street hearsay):

1. Male-on-male violence

2. Law enforcement (bouncer/police) - which has different psychological considerations and physical relaities

3. Female domestic violence

4. Female violence derived related to a stranger attack

The aim is not to get away from classical karate, but given data is available now, to find the  overlap of techniques of one of the above 4 categories with the broader bunkai set of classical martial arts – as depicted in the below figure and reviewed in the book 

“Street Fighting Statistics & Medical Outcomes linked to Karate & Bunkai Selection”. That review process most importantly not only states what is the top 7-8 likely street events that lead to a medically relevant injury, but also which techniques do not (and this, surprisingly to many, includes a broad range of commonly used kansetsu waza often displayed by karate-ka in bunkai).

Figure: A representation of the overlap zone of the pool of classical karate bunkai techniques with what street data and probabilities indicate actually occur. Taken from page 177 of “Street Fighting Statistics & Medical Outcomes linked to Karate & Bunkai Selection”.

Even in the days of the shito-ryu founder, Mabuni Kenwa who was a police officer in Okinawa & Japan, the bunkai for such classical kata were questioned as to whether they were practical or not from this Master himself (source: Mario McKenna brief biography of Mabuni Kenwa). Of course the police officers of that era did not have masses of police assault data and hospital emergency street fighting data, but we do today. In this video we talk to that data and compare to the classical kata interpretation.

As three examples of some high level data on violence, the differing violence categories have different violence ratios. Therefore a rational exists for technique biases in classes and curriculum design based on the potential need:

1. non-intimate (stranger) based female assaults have a 1:1.5 grappling to strike ratio

2. intimate attackers (husband, date etc.) for female violence, the ratio of strike versus grappling events is 1:1

3. male 9:1 strike to grapple need for injury based outcomes

Furthermore, bunkai sequences should flow with each technique being consistently  applicable to the defender's sex and violence category (outlined  in further detail in the book). For example, one should not create bunkai sequences that begin with a female attack entry (e.g. a single handed wrist grab) and finish with a male oriented technique (e.g. a throw requiring some power). Commonly people mix sex/scenarios in the display of a single bunkai sequence. 

With the above stated, the below bunkai list does not represent one of the four violence categories above (which we advocate for students in the dojo), but rather gives a bunkai set that is relevant to the top 8 techniques which produce medical outcomes in the street (see ISBN 9781471083969 for details) spanning all 4 of the the violence categories i.e. it gives an example of a generalist but street specific curriculum agenda. In summary, the below bunkai list represents:

11 bunkai from Bassai dai, with a strike to grappling ratio of 10 techniques to 5 (i.e. 2:1 favour of striking). 

Of the top 8 events in the street that lead to a medcial injury (not listed in this article), each appear the following number of times:

#1 – 3 times 

#2 – 2 times 

#3 – 3 times 

#4 – 1 time 

#5 – 0 

#6 – 2 times 

#7 – 3 times 

#8 – 2 times 

Of course the below are listed as Bassai Dai support/reminders for students that have participated in our seminars and read the above discussed book. The abbreviated 11 bullets below by no means convey an adequate description of a competent bunkai motion, nor supporting photos. However, even for those not familiar with an evidence and violence sub-category based approach, it should create some food for thought on how to go about the process (also see below for a 35min video download that walks through these 11 bunkai and the kata).

1. Break out of a cross hand wrist grab (female)

2. a. Block hook with left arm, upper cut (unisex; addresses #1, #2 of top 8)

    b. Opponent grabs lapel, right hand comes down on elbow joint while left hand goes up to cover hook, then right 

        hand upper cut (addresses #3 of top 8)

3.  a. Right arm "kansetsu uchi" to address a lapel grab, left hand upper cut, pile drive/throw (male; female if high skill level; addresses #3 of top 8)

4. Right arm "kansetsu uchi" for a lapel grab, combined with a break to the outside with left hand "kuri uke", choke with right arm from rear (male; addresses #3, #8 of top 8)

5. Left hand “measurement kamae” – right hand punch, follow with right hand cover a hook, left hand punch, left hand upper cut, right hand hits back of neck (if dogi, if not hook under arm for a throwing grip) and perform a throw with left hand guiding down the opponents hand (male – as pull down/throw unlikely for female but back impact will give an instinctive forward lean; addresses #1,#2 of top 8)

6. "Kuri uke" left hand, right knee kick, right empi, return again right empi (grab maybe) - (male; female if high skill level; (addresses #1, #6 of top 8)

7. Double lapel grab evasion, double lapel grab, head butt, face punch, pile drive/throw (male; female if high skill level; (addresses #4 of top 8)

8. "Kuri uke" for push, rear knee strike, empi right hand, left hand pushes arm down, right hand around neck for choke, left hand assist the choke (male; addresses #8 of top 8)

9. "Chudan uke" motion to release from single hand grab, rib punch  (female)

10. Catch kick and throw away (unisex; addresses #6 of top 8)

11. Right hand "uke", "shuto uchi" throat/jaw with right hand, right leg inside sweep right leg (or outside sweep left leg depending on opponent & positions) with right hand on head (if dogi, if not hook under arm for a throwing grip) and left hand assisting/guiding (male; addresses #1, #2 of top 8)

As a final reminder, the above Bassai Dai bunkai list does not cater to a sub-category of violence, it serves as an example of an across category approach. A category specific approach is encouraged as it would create the best training support for a given individual and can still pull from the pool of traditional, but street relevant tools, which karate offers based on street/medical statistics.