I don't think it was a "knee jerk" reaction. She was introduced as a total Mary Sue and was also used to make Adam look like an idiot. A lot of people had a bad reaction to that. It doesn't always take a lot of apperances to form an opinion on a character. ETA: She was also brought in as a series regular after a beloved recurring character was cut due to "budget" issues. That didn't sit well with a lot of people either.