I'm guessing you havnt worked in a corporate environment yet :)
if I paid you to rollback hundreds of accounts every day, I bet you wouldnt check items at all! thinking that blizz would is a tad naive imho
i have and still do this day work in a corporate environment, furthermore I work in a software developing environment.
Not a programmer, but an analyst and very familiar with coding, its limitations, and its simplicities.
for there to be a "red-flag" auto check on roll-backed accounts is childs play, very simple stuff here.
You start with one roll back, and keep a database of items (equipable items). At first you build this database, but eventually, and certainly before the point of seeing 10+ exact same mantis on the AH, even an auto rollback can easily red-flag an account and then require manual inspection if an item makes a "re-appearance", or a match to an item in the database.