CEV is one of the many flavors of total act utilitarianism (or average?

This is not just false, but something of a category error. Here is the CEV working paper if you want to read it. It's talking about a very loose class of procedures to select actions using the device of what an idealized version of some specified population would decide on under some idealized circumstances. The upshot of that for object-level normative questions depends on how the idealized process of moral deliberation would go. There's no necessary connection to any form of utilitarianism, or any other first-order normative account.