He agrees and repeats back the dive brief on the surface but has a seriously disconcerting habit of ignoring you underwater.
Is he really ignoring you or is it more a case of becoming "air headed" due to being distracted?
In my experience is usually the latter. If he's really ignoring you then you have a bigger issue and should disregard what I'm about to say:
In all cases of "air headedness" I've seen to date there have been a limited number of causes. My advice to you to start out with would be to seek the "reason" and not respond too much to the behaviour until you're clear on why it's happening. Just like 'debugging' a computer, once you know why something isn't working right, you can usually solve the problem. Knowing why is the key.
The reasons I've seen are the following (very short list):
- distracted by excessive thinking
- limited intelligence
- social discomfort (and/or other types of anxiety)
- young in age
I'll handle them one at a time:
1) Excessive thinking: This burns free attention. That should be obvious. We all engage in excessive thinking... and if you don't believe me then try to sit still and just listen to your breathing for 2 minutes and not think about anything. Most people won't go 15 seconds. It takes training to "calm" the mind and free up that attention for other things. Some people have more difficulty calming the mind than others and especially (in my experience) people who are more intelligent can fall into the trap of letting their mind go into overdrive when they're experiencing new things for the first time.
If your student had been a Kung Fu master instead of a Karate master then he would already be familiar with meditation. As far as I know it's not a well ingrained practice in some Karate schools but in others it is. Ask him if he knows "chi gung" (it also has other spellings but this way is easy to see how it's pronounced). Even if it's called something else in his Karate form he should recognise the word as a series of exercises that can be used to focus the mind/body through breathing. Ask him to meditate and/or do some kind of chi gung breathing before going under water and see if that helps.
There are other ways to improve ones attention span too but in my opinion nothing works nearly as well as meditation. The second thing that could work is to "invent" a task chain (which is kind of the way training works anyway). If his attention is drifting then increase the tempo. Also, if he's highly intelligent, try adding items to the task chain. Tell him that you want to see eye-contact every minute, that you expect him to follow (or lead) and define those roles in terms of tasks (task chains) like stopping and communicating changes in depth, tempo or direction every time he makes a turn.
He's a Karate guy so you might consider using Karate level consequences that he can understand. 10 push-ups for air-headedness, 50 for dangerous loss of communication. Also, remind him (on no uncertain terms) then when he's teaching karate that he expects out of respect that students pay attention and that you expect that from him too! Make him focus on that. This might sound hard but it just puts it in a familiar context for him. I did something similar once with a guy I had who was a soldier and had this problem. Connecting it to a known learning context by, in my case, deliberately sounding irritated and short when he wasn't paying attention, actually helped him focus. I was also very direct and "unsalted" in my feedback which is something he was accustomed to and it helped him learn faster. Maybe this could work for your guy too.
2) Limited intelligence: Some people just don't have the mental horse power to keep up with a continually advancing task chain. They often find even a moderate tempo during training overwhelming and it can (from what i've seen) cause them to sort of "shut down". In this case, the idea would be more to slow down than to speed up (see why it's so important to know WHY it's happening first?).
3) Social discomfort: I've seen some people who were difficult to communicate with; both above water but especially under water because they had a kind of social discomfort about making eye contact. Eye contact is very important for communication under water and some people can start to *avoid* communication (look away, or even swim away) when faced with the prospect of having to make and hold eye contact with another person. This may not be the only anxiety level issue that can result in this behaviour but it's an obvious one.
4) Youngsters: I'll admit, I hate training kids under the age of about 14, because on top of all the above they can also have trouble evaluating and responding adequately to risks. I think this has something to do with a still-developing ability for lateral thinking but regardless of the reason I've seen more kids go bimbling off on their own under water than adults. Somehow the point that staying together and keeping in communication is important doesn't seem to always take seat. What works in this case is, alas, "follow me" and to present yourself as being completely in charge so they are completely focused on you. That works with kids but won't work as well with most adults. It's also not something I would recommend as a long term solution because it is somewhat contrary to the point of the course (to create an independently capable diver) but regardless of stupidity of it, some parents still take kids that aren't ready for scuba training so making yourself their main focus can be an effective stop-gap measure to get them through the initial stages.
I don't know if this will work with your guy but I bet it will. As a martial artist he has years of training that involved mirroring on a strong leader so taking a more prominent position as the leader may help him to follow better. For example, you could introduce skills while swimming and say "follow me, watch me do exactly as I do". You might find his focus improves as long as you keep playing monkey-see-monkey do with him. Take frequent breaks to the surface, give him concise and brutally accurate feedback in 30 seconds and them make him try it again and again. In other words, he's good at Karate and he's spent years learning it so it might help to model your approach to the scuba training somewhat to mirror the "follow the strong leader" approach.
Finally, I'd like to urge you not to give up on this guy. He's as good for your development as a teacher as you are for his development as a diver. This could be good for both of you.
Good luck.
R..