Even those that JUST do Olympic sparring, are still in a better position to defend themselves if they did nothing. However, compared to other forms, if you want SD, one must train in that system which does SD & nothing else. Even ITF TKD would not fit this bill, as there are more efficient SD systems. However ITF TKD is an Art form of SD, that has other more important goals & other aspects, including a sports aspect that competes in 5 categories.