Wayne, it does not matter what kind of blade it is, the durability level controls the functional geometry. A higer durability allows a more acute edge given the same set of tasks. Or given a set geometry, a more durable edge allows a wider scope of use.
As for chopping, assisted chopping is often done with very small blades, and as for axes, a wood cutting axe with have a much thinner edge geometry than the Camillus EDC. The only axes that you will see with edges ground as thick as that are either for root cutting or throwing as otherwise you are wasting cutting ability.
In regards to general cutting, there are lots of things that will quickly damage the edges on knives with low levels of ductility and impact toughness. For example, if you are cutting materials that are not NIB, odds are high that there is going to be a significant concentration of inclusions. Cut up rope that has been used and exposed to the elements for example, or breakdown used cardboard boxes.
Even cutting clean materials can also break apart edges with low durability. I have done long cutting sessions on clean cardboard 10 000 cm, and have seen several edges blunt by fracture. You have to consider the geometry of the very edge, we are talking about a very small piece of steel. Even if the edge is damaged to only 1/64", it will still be so blunt you can't cut much of anything with it.
-Cliff
[This message has been edited by Cliff Stamp (edited 05-28-2001).]