He argues that evolution and creationism are both theories and that, even though we may agree with one but not the other, both theories deserve consideration. As a scientist, I find such an argument untenable.
In order for a proposition to be considered a theory, it must be supported by a substantial body of scientific evidence, and it must offer testable hypotheses.
There is no scientific evidence in support of creationism, and it does not lend itself to testable hypotheses.
As such, creationism is not a theory and, in fact, it is not even a hypothesis. Creationism is a belief.