Collapse is the sudden change in wave function after a measurement. Unless otherwise stated, I will assume that neither the wave function nor collapse are necessarily physical, and are just calculational tools that are part of the experimental success of quantum mechancs. Collapse is in almost all major textbooks except Ballentine and Peres, and is used in a standard way in the Bell tests. Peres suggests that collapse can be replaced with coarse-graining. We know that collapse is verified by all experimental data to date, and that coarse-graining, if successful, must make exactly the same predictions as collapse. I think it is an interesting idea, but I have only ever seen it in Peres. Can coarse-graining without collapse successfully reproduce the predictions of quantum mechanics? In particular, can one do the coarse-graining without collapse explicitly and recover the correlations for the Bell tests? Is the coarse-graining in a Bell test a local procedure?