There are a few things I know Jerseyrodder, one is that the cylinder walls are measured with a micrometer for a certain size. Let's just say for example your stock bore in your engine came out at 3" exactly. Now the engine has 100,000 miles on it and it has loosened up the piston in the cylinder. There is an amount of wear that can be tolerated and honing will fix, say .04000 of an inch. They will measure the cylinder all the way to the bottom of the stroke because too much tapper is bad too. After that certian amount, you have to bore it out. I'm sure there are fellows here that can give you exact dimensions.
Also scaring such as lines in the cylinder walls can mean metal has been scratching there and you will loose compression down through those scratches.
I am no expert but there is very little tolerance that a ring will absorb before you suffer power loss and eventually start using oil.