IIRC, Hillary has her own BP issues in her past. Perhaps this is why she didn't pursue this avenue more aggressively.
Hillary was a true Alinsky fan (in fact, I believe she even wrote her thesis on him), but she appears to have matured out of it a bit. She’s still a raving leftist, but I think she and her husband have gotten enough out of the system so they don’t hate it. But I’m sure she probably did worry that her old stuff would be brought back against her if she challenged Obama.