User blog comment:Burk89/Hidden 31 wells in revelations/@comment-188.205.37.158-20120110151114/@comment-5276769-20120823070642

There is no way the game makers would do something that stupid. The probably didn't even expect people to search for the wells in the first place. The supossed "4" missing covered wells are most likely DLC content, ex. "Ezio will travel to another city, maybe one that you can send your assassains too." or, that the total count is not accurate and 27 is the true total.