I realize this thread is a few months old, but I have just joined the forum!
I think I will be a good study candidate for the accuracy of this chart. I have only one 90-day late from Sallie Mae in May of this year after having a bankruptcy in 2008. My credit score when I purchased my home last August was in the 650's and once this late hit, Walmart reported my score to be 607 the first of last month. I am waiting for that to udpate now.
According to my current score, the chart would be pretty darn accurate. I have a plan in place to have all of my balances down to less than 10% by my birthday in late July 2013. My current utilization is around 88% and I knocked one off the first of this month in full. I have Sallie Mae working on my 90-day late and have had numerous conversations with them, but don't believe I will be able to get it deleted. I will keep trying but they seem pretty sure of themselves.
Any way, I will try to update here in this thread to track the further accuracy of the chart...if nothing else it will be fun to watch !!