Things such as calling women "girls" but not calling men "boys" or referring to a collective group as "guys" are forms of subtle sexism that creep into daily interactions. The study helps not only identify which forms of sexism are most overlooked by which sex, but also how noticing these acts can change people's attitudes.
D: funny, I've been annoyed at a counter-example for years.
Somehow, it is more socially acceptable to insult a man based on his genitals than doing the same to a female.
The usual reflexive knee-jerk reaction is, "well, that's DIFFERENT" but it is the same thing.
An IAL that requires optional affixes to denote details about a person would make such considerations explicit, and presumbly more consciously done.