"No Fault Policy" looks really stupid and not convenience to customer. "No Fault" does not mean no fault for you and others in accident. your both still have fault judgement by both insurance companies. The only difference is that your insurance pays you and the other one's pays him.
Why they do this way? Because from a long period of viewing, for the regular policy, say insurance company A and B, most likely the company A pays to company B at the same amount as the company B pays to company A for the long period(say one year). So they take it easier, make the agreement to pay their customers themselves. But for customer, It is really not comvenience.
Your insurance will not increase if your fault is at 0%.
But sometimes it depends, such as if you claim many times within a short period, they may increase yours even you are not at fault. Say two months, you claim three accidents which are no fault with you, they may increase yours.