After class today I was thinking about the differences between our copyediting marks and our proofreading marks. My question: If we are using proofreading marks do we always use them in addition to the copyediting marks? For example, you couldn't use the proofreading mark alone to transpose text. You need the copyediting mark to indicate which text is to be transposed and then you can include the proofreading mark in the margin to indicate that something needs to be transposed on that line.
I also did some googling, and the title link is to an article that differentiates copyediting and proofreading.