As the thread starter, I vehemently disagree. Most of the posts here are simply listing a prospect the poster thought was going to be good, and then he failed. That's not a blind spot, that's a wrong predicition.
A blind spot is the continued overrating of a player despite ample evidence to refute that rating. There was a time when many Sox fans wouldn't have traded Trot Nixon for Sammy Sosa; that was a rumor that was very much in existence (even if the actual possibility of it was not), and anyone who wouldn't have made that trade was suffering from a blind spot.
The term blind spot can mean different things, for sure, but I thought I was pretty clear in what it meant for the purposes of this thread in my original post. I then jumped in to clarify a page or two later because people kept running with the hoo-boy-I-thought-this-failed-prospect-was-going-to-be-good meme, and that didn't work, so I gave up. These things sometimes take a life of their own, whatever.
The only reason I came back was because Nixon is one the best examples in this thread of what I was looking for, so I don't want to see it dismissed.