… teach Darwin's theory the way Darwin would have himself, as an argument.
This may be the dumbest thing I'll hear all day. Nearly every word in the sentence fragment I quoted is wrong. On the Origin of Species is a long argument, it's true – but it's an argument packed tight with research. Darwin spent decades writing it, gathering evidence, interviewing dog breeders, pigeon breeders, plant breeders, breeding pigeons himself, experimenting on how long seeds remained viable in saltwater (to see whether floating seeds could colonize oceanic islands), reading research from areas he hadn't seen, collecting wild animals, geological specimens, and marshaling that all into what he always considered the abstract (at 490 pages, a remarkably long abstract) of his Big Species Book, which he never finished. It is an argument in the sense that it is a presentation of evidence for a particular model.
Students should learn about modern biology the way Darwin did, through experiments, exploring the primary literature, and evaluating the actual evidence, but not through sophistry. This is the problem with how DI and it's paid hacks approach the teaching of science. Science isn't an court case and it isn't an encyclopedia. It didn't stop with Darwin, and "Darwin's theory" should only be taught to the extent that students learn what's changed in the last 150 years.