No woman should be blamed for being raped, but that doesn't mean women should not take responsibility for their personal safety.
Not all rapes are preventable, but some are, and the most important defense is to be observant, use and trust your judgment (which means avoiding getting into a situation where you are so intoxicated that you can't look after yourself) and exercising caution about who you go home with, get into bed with, etc.    As to dressing provocatively, that's an individual choice but it can be a risk factor in that it sends out signals that can be misread… you don't know the mindset of the person who's picking up on those signals.
When I was young and naïve – having recently left the small community where I grew up, I had some difficult incidents with guys who invited me to their apartments for dinner or a drink and then put the moves on – in a few cases very aggressively.    I didn't get raped, but I did feel threatened and uncomfortable.    I learned to be careful about who I went home with – to read body language and other signals, and it helped me to avoid such situations in the future. And no I didn't become paranoid, just much more aware.    Now, If I'd gone to dinner at somebody's house and been raped would it be my fault? No. But being aware of the possibility made me much more careful about whose house I had dinner at.    It's entirely possible that I could have misjudged somebody, thought they were trustworthy, gone to their house, and gotten in trouble, but as I said, not all rapes are preventable.   
You could say that about most crimes. I always felt that my neighborhood was safe and often didn't bother to lock my car. Then one day somebody stole all my CDs from the unlocked car in my driveway. This made me aware of the risk, and I now lock my car. Was it my fault my CDs were stolen because I left the car unlocked? No, but I doubt the kids would have bothered smashing the window, and had I locked the car, it might have prevented the theft. Not all crimes are preventable, but you can reduce the risk.
There's a difference between blaming the victim for being raped and encouraging women to look out for themselves.    In an ideal world, they shouldn't have to, but the human race just hasn't reached the point where we can always trust everybody.