Sorry to invade this thread with knife content but...
The Ion-fusion, or Buck cote should actually do very well on cardboard. Because of the abrasive nature of CB, it wears away the exposed steel of the blade. Just like on a non coated edge, it makes the edge dull right? Thats because it is wearing it away. (This is all at a microscopic level ok?)
So, with the coated blade, as the steel wears away, it exposes more of the coating, which is off the scale in hardness. Therefore, the coating is doing all the cutting and as the blade wears away, it just exposes more of the coating. Remember this is a one sided edge.
When we tested the stuff in the lab, we used an abrasive paper and those blades would cut forever, getting slightly dull over time and then, suddenly, get sharper! When they "got sharper", that was when the blade steel wore away to the point to where a new edge of coating was exposed and off it went.
Hope that makes sense and you find it interesting. :yawn: