[glenstein]

>I think in this context it means that adding a deity into the explanation is adding an unnecessary extra element where none is needed.

I want to reiterate that I think the side you are arguing for is ultimately the "right" one, but I'm not sure I buy this argument.

Sometimes parsimony is having a fundamental thing that other things "reduce" to, that other things are explained in terms of. Someone intent on adding a deity can insist that it's not merely one extra thing among a dozen things. Instead, it is the one fundamental thing that gives rise to the dozen things. And therefore is more parsimonous.

I wonder if the right thing to do here is bite the bullet and admit that, yes, such a thing would be simpler, but you merely think you have a simpler thing when really you have smoke and mirrors.