It's all about durability of the edge. Japanese sushi knives have very small
angles and cut like razors. But they must be handled carefully and used only
to cut fish. Some people who sharpen their own knives put small angles on
them ..they cut wonderfully but require frequent touchup. A broader angle
will last longer without repair and will withstand better being put in the
dishwasher, being knocked around in a drawer with other knives, etc. and so
this the factory edge that many knives get.

"John Bailey" wrote in message
...
Just to satisfy my own curiosity. If a blade of any sort is sharpest when
the angle is very shallow, what would be the advantage apart from edge
durability to using a larger angle? excluding cleavers which I imagine
would be used for chopping rather than cutting, so would possibly need a
more robust edge I have found my knives cutting more smoothly since I got
a
steel, but I assume the smoothing quality of the steel may have something
to
do with reducing the friction between the food and the blade rather than
improving the edge on a freshly sharpened knife.

John