Dear Lady in the Alero,
I want to cut you some slack and assume that your memories of Driver's Ed are fuzzy. I would like to refresh your memory. The large, octagonal, red sign with the word "STOP" written in white lettering, when it is facing you and you are in your car, means "STOP."
Now, I realize that the guy on the motorbike who expected you to actually, you know, stop, should have known better. It was clearly his fault for continuing on as though he didn't have a stop sign. (By the way, he didn't have a stop sign).
Also, I don't know much American Sign Language, so I'm not sure if the sign you were using really means "I'm sorry, you go ahead" but where I come from, it's not so nice.
Also, all of us behind you in line at the lights thought that your hair looked fine the way it was. I mean, it was just from the back and we were all waiting for you to notice that the light was green, but really, your hair looked fine. You didn't need to worry about it.
Oh, yeah, it was really nice of you to just stop dead in your lane like that when you couldn't figure out which lane you wanted. That was a lot of fun, as it let me test out my seatbelts. They work great! Thanks!