At the risk of being controversial, isn't there also the choice not to implement autocomplete and then avoid the above conundrum, especially once you factor in the fact that they can't possibly catch all combinations of words/letters so a grey list isn't actually an effective solution either, other than it provides a we tried defense.

The ultimate problem being some subset of consumers want autocomplete and some subset will retain the right to be offended and some subset will be both of those?

EDIT: And at what point does accidently sending male chauvinist pig to your boss because of autocomplete absolve you of the responsibility of reading the message before you send it?

Is there any reason apple can't give us the choice of.

a) No autocomplete.

b) Autocomplete with greylist.

c) Autocomplete without greylist.