Mike wrote:
I'm not aware of an official method, but I would make a cut with it,
then switch to a known sharp blade, and make another cut from the same
stock. You should be able to feel if it's sharp or not.

Look at it closely -- if it's sharp just like a blade the tooth edges
and corners will be crisp and not rounded. Carbide, of course, isn't
quite a sharp initially as HSS but general precept still holds.

--