You better be able to defend it after the attack - so don't stretch it. In other words, if the guy's guilty of A and B, don't make him guilty of A, B, and C. That's what a lot of people do.
I came to the realization that I started dating my now-wife junior year of college, before you actually went on a date. You didn't take girls from college out to dinner. I've never been on a date. I've never been on a date where I didn't know the end game. I've never casually dated someone. I've only been out to dinner with the woman who would eventually be my wife.