Atemi is an actual strike. In fact there is a separate art called atemi-jujutsu. The diffrence between atemi and a strike is that atemi is used to create balance, rather than just kill someone with it. The most common type of atemi we use is metsobushi, a strike with the middle nuckle between the eyes. In aiki atemi is followed with a tecnique. Yes it can be used to distract someone before the throw occurs, in the same way a kiai is used etc etc. But atemi must connect when truly practiced. We do seminars purely on atemi sometimes, you feel what its really like to have a whole tecnique put on you along with an atemi which connects. To clarify my above statements hijiate (elbow strike throw) is not considered atemi? Gozo shioda I think concentrated on atemi more than an other high ranking I know. In training for us it is always stressed that we must atemi or your tecnique wont work if in a static situation. That is why in rensoku dosa there is so much striking in the yoshinkan.