I don't use any sort of numerical data to make my picks. I try to find a balance between the star-power in the bracket and being realistic to who they were at the time. I'm glad you brought up the 2011 bracket because it's a great example of my thought process..
Yes, there are three champs in that bracket, and another finalist. However, DT, St. John, and Welch were all Freshman in this tournament. Wunderkind David Taylor had been on a bonus tear during that season, but many were still wondering how he would do against a guy like Steve Fittery, who, while very good, isn't a name many would know outside of hardcore fans. Adam Hall as well, many probably remember him as a very solid multi-time AA, but he's far from an all-time guy and was the top seed going into the tournament. IMO it's hard to consider a bracket for All-Time best when the top two seeds aren't particularly noteworthy.
It's far from perfect as it's really my subjective opinion that is leading the cause, but that's why I am interested to hear others make the case for other years.
I do the subjective analysis based on research and my personal bias, and then @Wrestleknownothing comes with the hard numbers.
PS: Tomorrow has one of the most intriguing brackets so far, imo! Stay tuned.