Technically you are right 15% is from judges and 25% is peer assessment, but that results in 40% of the people filling out these scantrons from 1-5 and the peer assessment is comprised of law professors who are lawyers and may have been or currently act judges so in reality it is 40% and again it is just based on these lawyers and judges or if you want to make it sound like more work was put into it lawyers/judges and legal academics filling out forms rating schools between 1-5 and I guarantee you not one of the judges has been to all 200 ABA schools in their lifetime yet alone in any given year.
You may also be right that it was not 2011 when the switch occurred. I know in 2006 when I was applying they did not count past 100. I think the change might have happened in 2009, but again once I was out of the law school bubble I paid very little attention to the rankings. I would be interested to find out when the change happened though.
Again, if you want to take U.S. News seriously by all means go for it, but if you are thinking about applying or currently in law school go talk to real attorneys and see how they feel about them. You might be in a market that really cares you might not, but I would encourage you and any other aspiring or current law student out there not make life altering decisions based on a magazine, but it is a free country and I am just an anonymous internet poster so do what you think is best.