It just proves...
what we already know: 1) men readily think about sex/mating/women; and 2) men have a one-track mind. So, in this study, #1 was primed to kick in, and then of course #2 reduced their performance on a test which gave them no personal benefit. Why concentrate on a stupid Stroop test when there are more pleasant thoughts running through your mind? "I bet she has big -- red! no, blue! Aaaaaaaaaaaaaaa!"