When i did taekwon do, we did 3 step, 1 step and free sparring. basically, with the one step, we would stand out of reach, then the attacker would to a high section punch, and the defender would move in and perform the counter. however, in shotokan our one step (or ipon kumite) is done standing quite close, the attack is done (either high punch, mid punch, front kick, turning kick or side kick, from either leg leading) and the defender must defend and counter as the attack is being thrown. I feel that this is more realistic as in the real world you dont get the luxury of someone holding their arm out while you walk up to them and counter. are other tae kwon do's like the one i did, or are they more like the shotokan method?