Had a guy hooked up with metal handcuffs, he started kicking, so I flexed his feet together (two flexcuffs, interlinked and snugged up around his ankles), got distracted for a second, next think I knew I got kicked in the side of the head. He had managed to bend the little metal blade back the wrong way and was free.

You want to hear scary, I have seen guys, smallish guys, who were on PCP break the chain on a pair of Peerless steel handcuffs, with the cuffs applied behind the back. Then things can get out of control very rapidly...