Hambourger's design argument

Hambourger argues that even if there is no evidence of interference by a designer in the course of evolution, we have to consider the fact that living creatures are made up of genetic material that reproduces after its kind, but not exactly. We could have reproduction that only produces exact duplicates, in which case evolution would be impossible, since there would be no variation. We could also have genetic material that changes very rapidly, in which case speciation would be chaotic, and evolution would also be impossible. That fact that genetic material changes gradually is the only scenario that makes evolution possible. But why did we happen to have genetic material that mutates at just the right pace? Doesn't that imply a background designer?

For some critical comment, see here.