Eh, look at the journals for the reasoning there. Many editors and reviewers don't have the time to untangle multi-variate effects and make certain the math was right. Maybe that was because they can't do it themselves, but usually if it is that complicated and interconnected and you come out with a 'clear' picture, odds are that it was an error. I'm NOT saying that is in fact true at all. However, most editors get so very many submissions every day that they take the easy to understand papers with clear results and pathways over the harder to understand ones that are more likely to have errors in them as they are more complicated. This feeds backwards into the grad schools and then only simple pathways and mechanisms are encouraged and nurtured, while complex ones are left alone in the publish-or-perish environment. And yes, this is BS, but that is how grants get funded.