Explain the value of a really sharp point and edge, the latter, particularly with a double edged knife, being as much to prevent the knife from being seized as for slashing.
A double edged razor will last a lot longer than disposable razors.
Therefore the deficiency of pre-Cambrian fossil and the sudden emergence of Cambrian trilobite are like a double edged sword posing threat for the very foundation of Darwin evolutionism.
However, it can be a double edged sword.
