I still don't see how paper is more damaging to a knife edge than, say, a wooden cutting board. Or cutting apart chicken pieces.
I've only got a couple of good knives, and I try to take good care of them, so I'm always interested in learning about such things.
First, I have to say this: You shouldn't be using a wooden cutting board due to sanitation concerns. Plastic cutting boards can be soaked in bleach, wooden ones cannot. If you do use a wooden cutting board, you should never EVER use it for meat or chicken as it is porous, and will absorb any contaminated juices and transfer them to other foods.
Now, on to the real subject of your post. Paper, due to the condensed fibrous nature of it, will dull --any-- blade (even scissors) faster than most other materials. It causes uneven scratches in the blade (as opposed to other food substances that cause even wear) that can be almost impossible to re-hone out of the metal. The other thing is that the thinness of the paper, combined with the pressure needed to cut through it, causes the edge of the blade to curl over ruining the bevel of the cutting edge, and requiring extensive re-honing. Believe it or not, cellulose is an
extremely tough material, and the way it is compacted and compressed into a piece of paper makes it even more tough. Unprocessed wood is much much softer than paper is.
This is not a phenomena that is isolated to the culinary world. Quilters don't use the same pair of scissors to cut paper as they do for fabric for the very same reasons a chef won't use his chef's knife to cut paper -- paper ruins the edge, and makes the blade less effective on softer items (which require a sharper blade, by the way, to be cut well).
You can do simple experiments at home to verify what's been said here. For example: take a stack of paper equal in thickness to a food item, and try to cut through it with a knife (don't use an expensive knife!). Using a different knife (you'll have pretty much ruined the other one), cut through the food item. Note the difference in difficulty.
For a more in depth study, you'll want a magnifying glass or microscope. Take two knives, sharpened equally, and examine the blades under the microscope (make special note of the bevel). Use one to cut paper, use the other to cut food. Look at the blades again under the microscope and note the differences in decay of the bevel (curvature, blunting, irregular indentation, etc.).