I was looking at some of the research mentioned in footnotes for this project and noticed some of the user data came from research in 2004-2008 when the site was quite different than it is now. Other research came from surveys or studies done several years ago.
So, when I'm looking over these usability tests, I'm surprised not to see any date for when the testing occurred. Was this before, during or after the VB interface was rolled out? This would be useful to know, even if it is just a date range (like Dec 2012-Jan 2013).