Good point.
Perhaps I should have said "its impossible to intentionally maximise anything other than your utility function".
People can intentionally maximize anything, including the number of paperclips in the universe. Suppose there was a religion or school of philosophy that taught that maximizing paperclips is deontologically the right thing to do - not because it's good for anyone, or because Divine Clippy would smite them for not doing it, just that morality demands that they do it. And so they choose to do it, even if they hate it.
There are a lot of explanations of consequentialism and utilitarianism out there, but not a lot of persuasive essays trying to convert people. I would like to fill that gap with a pro-consequentialist FAQ. The target audience is people who are intelligent but may not have a strong philosophy background or have thought about this matter too much before (ie it's not intended to solve every single problem or be up to the usual standards of discussion on LW).
I have a draft up at http://www.raikoth.net/consequentialism.html (yes, I have since realized the background is horrible, and changing it is on my list of things to do). Feedback would be appreciated, especially from non-consequentialists and non-philosophers since they're the target audience.