Considering that concussion risks are compounded by repeated injuries, and that the risks of concussions can include slower reactions, impaired cognition, and even changes in mood this should be something that concerns non-military self defense athletes as well.
A new military study suggests that some soldiers suffer mild traumatic brain injuries even before they go to war. These concussions, as they’re also called, can come from taking “combatives” classes that teach hand-to-hand fighting during the soldiers’ training…
The study looks, in part, at soldiers at sprawling Fort Hood, Texas, one of the Army’s main centers for basic training. The preliminary findings, which NPR and ProPublica have obtained, suggest that a soldier got a concussion in those classes every other day, on average, over nine months.
“The more hits your brain takes, the less likely it will be that you will have a full recovery,” said Dr. Alex Dromerick, director of neuroscience research at the National Rehabilitation Hospital in Washington, D.C. Dromerick, who has studied brain injuries with the military, didn’t work on this new study on concussions. But he says that based on our description of the findings, they raise a troubling scenario.
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are available here.
Fight Sciences Research Institute blog 
Maybe its because a lot of their training is more geared towards competition than scenario based training- the IDF as far as I know does not do competitions- and when they train with lots of force they wear protective gear.
http://www.idfblog.com/2012/03/21/morning-bruise-krav-maga-training-mind-body-spirit/
This is how some Israeli soldiers train to combat situations they may encounter while on leave-
From this video it looks like there is significant concussion risk associated with these activities as well. I would venture the say that as testing for mild brain traumas gets more sophisticated and cost effective people will have to just accept that intense training comes with significant risk for head trauma-nd that this will hold for both sport and scenario based training.
Head gear can be a big help, but it can also encourage more intense head shots. Rapid redirection of head motion is not buffered by head gear and itself represents a significant risk. Additionally the added weight of head gear is likely to increase the risk the neck. Vertebral artery dissection is an often unrecognized and under-reported training injury that can result form whiplash type motions of the neck. Coaches need to be aware of these risks and not use protective gear as a license to let things escalate inappropriately.
It is interesting to note that soccer players often show evidence of repeated concussive injuries from “heading” the ball so it doesn’t take much to begin to cause problems. Of course no training is without risk, but it is a good idea to know the risks and possible consequences so that you can make informed decisions about what sorts of training is appropriate for your lifestyle.
That is why the military instructors go through a complete course that contains how to deal and prevent injury- the IDF’s combat fitness school is located at a closed off area at Wingate Institute (Israel’s premier sports science university)
Wingate Institute’s training goes beyond pedagogy- they learn about anatomy and physiology, first aid, sports science, injury prevention, developmental psychology, etc.The IDF’s krav maga instructor course I think is six weeks long. Nothing is perfect- but your caveat is very important Bob.