I tend to agree, but not with your particular example; the boundry between how you manage a resource and what you do with it seems like the perfect place to put

I tend to agree, but not with your particular example; the boundry between how you manage a resource and what you do with it seems like the perfect place to put an abstraction. The file mingling can be in one big function, but there are benefits to separating it from the open/close logic.