Not to be captain butt in, but sometimes they'll just smart price a low performing website, usually they do they whole account, but in retrospect they wouldn't do the entire account if you had 1 very well preforming site and one low preforming site.
What the... :O I thought it only smartpriced the website performing low. Are you guys sure about this?
No one outside of Google is 100% sure about these things, but that is the best information we have. This came from something a AdSense team member told publisher back in 2005. I have tried to gather all the information about smart pricing in my smart pricing FAQ.