Can I enter and leave Ireland on different passports without a hassle?

I am a dual national and have heard you should leave a country on the same passport with which you entered. I'd like to enter and leave Ireland on my Irish passport, but what's confusing me is having to deal with U.S. customs at Terminal 2 in Dublin Airport for my return flight to the States. I'm sure U.S. customs officials will only want to see my U.S. passport and will disregard my Irish one since the U.S. government doesn't recognize me as an Irish citizen.