There are a few other ways to get cats to lose weight:
Feeding wet food - it's not as calorie dense as kibbles
Feeding set amounts divided into 4 small daily meals and feeding like that means that all get finished fairly quickly and you can feed the glutton with the others
Having said that, I have a girl who was born to a feral mother on a rubbish dump and is so food driven that she tamed herself. When I try and limit her intake, she goes next door to eat the neighbour's cat's food. She remains a little blimp. Do take the teeth out, 10 isn't that old and you will have a much happier boy. Bacteria from dental disease can damage both the heart and the kidneys. Omega 3 oil is very helpful