To be honest, I suspect most attacks don't begin with a man leaping out onto the back of a woman, but with conversation and coercement. The attacker wants to avoid you fighting as much as you do and will sweet talk and push into a rape.
when I was 14, I this happened to me twice in a town centre, once in broad daylight. I was lucky nothing beyond groping happened, but in both cases the man sidled up , sweet talked , took my hand and `nicely` lead me away. It sounds strange but this over-rode my instincts to be violent because he was talking and I didnt know how to handle it. I did what many teenage girls do in this situation and that is to go along with it. It took me many years to understand why I did this, but I know the exact reason now. it is this:
When a woman is under attack from a much larger man whom she has little chance of escaping, her bodies first instinct is stay alive. this does NOT mean running or shouting or causing in any way, the attacker to get scared, aggitated or violent. The bodies best way of ensuring survival is to pacify the attacker and comply, and to ensure that he understands that should this case come to a court of law, you will have no way of proving a rape took place because you said yes. Thus, with this all on his side, he is much less likely to kill you.
I don't know what self- defense courses teach, but this is a huge mental hurdle for young women. The bodies survival instinct is different to societies instructions. Im not saying women under threat of rape should comply, Im simply pointing out that instincts can literally make you submit even if your mind is screaming at you to run. I just wish chauvanist judges understood this factor whenever rape cases come to court and the girl is accused of `wanting it` because she said yes. Men have a huge mental power over a woman in a vunerable situation.
I was extremely lucky in that the man couldn't find a park and lost interest. Unfortunately my own experience is not even rare.
also, I have a question to ask people who state that doing a self defense course makes you look more confident and therefor less likely a target - what evidence based research do you have to back this claim up? where are the statistics. without them I am not prepared to believe that these courses help in that manner.