Posted By:
Jeff D.I'm not sure what "it" refers to in your statement "...the fact that auction houses are not disclosing it," but there ARE auction houses that do in fact disclose cards as possibly trimmed and recolored. I've seen REA do it. Here are just two such examples:
http://s210975194.onlinehome.us/auction/2006/167.html
http://s210975194.onlinehome.us/auction/2005/208.html
In this description, the cards returned by SGC and not slabbed are disclosed in the "Four Ungraded:" section about halfway down.
http://s210975194.onlinehome.us/auction/2006/90.html
I would be surprised to hear anyone say that they are not interested in knowing if a raw lot they are bidding on has ever been returned because of some kind of alteration.