This is actually pretty cool, I just have one complaint, it's let's you do anything even create impossible scenarios. I was doing one and it let the Eagles win the NFC Championship game..seriously?
It is pretty awesome. By using this tool, I found a scenario which the Giants can still win the NFC East and eliminate the Eagles out of the postseason. The Giants can still somehow get the #3 seed but both would take ALOT to happen. Your right though crowned, the yahoo playoff scenario simulator does create some near impossible scenarios that would create quite a bit of teams falling off the face of the earth in the last three weeks of the season in order to happen.