To all the sarcastic commenters here, sounds like none of you have ever been unlawfully cuffed. I'm happy for you. If you or a loved one ever had been, you would be thankful that products like this exist.
So your argument is that because this product does not help with every situation in which a person can be bound — it is useless? I don't understand. That's like saying that having a spare tire in your car is useless because you might overheat.
% of rapes involving handcuffs
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% of rapes standard handcuffs used in such a way that both the keyhole and key are accessible to the hands
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% of rapes where the victim is left unattended and fully clothed (presumably the key is in the clothes or keys) long enough to unlock the handcuffs
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% chance of victim remembering to clip the handcuff key to their clothing
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% chance escaping from handcuffs will result in a better outcome for the victim
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% chance victim is not under constant intimidation and control of the perpetrator
Given that the first number - rapes that involve handcuffs - seems almost undetectable and the chances of a successful beneficial escape are quite low, I'm going to say handcuff keys are the equivalent of a tin foil hat as a rape prevention tool.
Is that a really a frequent enough occurrence to justify always carrying a handcuff key? I'd say that's likely to happen to your average skateboarder about once every thousand lives. You might be better off learning self defense tactics and avoiding being handcuffed in the first place. If you were manhandled enough to be handcuffed, you're unlikely to get very far with a key.
It seems to me that there's not a lot of cases where removing the unlawful cuffs will actually improve your situation. It seems like it's more likely to get you beaten/tazed until you stop resisting.
The "mitigating mass arrests" scenario I mentioned is one where it could help, though.
