Hi Tim,
I can understand what you are saying here, but it's not right, I'm afraid. A 10A cable is designed to carry 10A comfortably indefinitely. It has quite a high factor of safety built into the design. A 10A fuse is designed to burn out when a bit more than 10A is passed through it.
Having said that, your approach is erring on the side of safety. I wish all others would do the same.