Yes, I was (improperly) ignoring the typically backward-looking nature of act utilitarianism. I kept saying "maximize expected utility" rather than "maximize utility" which resulted in true statements that did not reflect what act utilitarians really say.

I blame the principle of charity.

EDIT: And if I were being really careful, I'd make sure to phrase "maximize expected utility" in such a way that it's clear that you're maximizing the utility according to your expectations, not maximizing your expectations of utility (wireheading).