I have never flown with Iris personally but one UA flight attendant told me some stories about Iris not being "all there" all the time. She apparently lives in Hawaii and is based in SFO. Once on her way to work, she got to SFO and thought she had already done her trip and went back to HI on the next plane. In another case, the captain had alerted her to some flight security situation that she was supposed to communicate to the rest of the crew, but she forgot to do so. With stories like these, I'm beginning to think that a company should be able to force a person to retire at a certain age. After all, at some point you have to make room for others as well and not only think about yourself. I know many older people who are very competent and keep working, so of course there are many arguments against it as well.