I don’t think I’ve ever used a can opener with any kind of confidence or skill. It’s maddening. I always feel like I just woke up after the Zombie/Nuclear/Plague/Religious Apocalypse, and am trying my best to open a bloated, mystery metal can with a rock, a twig, and a tailpipe from an abandoned Toyota Camry, all while doing my (second-rate) best to avoid both slashing my fingers AND sloshing the internal contents of the can all over my surroundings.
Actually, strike that – I’d have a better chance of success in the latter scenario.
Might be time to head to the junkyard.