This article from Financial Advisor Magazinesays "...lenders are creating potentially illegal difficulties in getting accurate records of their payoffs of the loans so they can apply for cheaper financing and making processing errors."
By the way, if you want a handy list of every loan you've ever taken out, and who bought them when you consolidated, go to the National Student Loan Database System site (here) and sign up for your User Name and password.
To finish the sign up process they snail mail you a confirmation code, so get started early.
I'm busy working on my blog posts. Watch this space!