That's the sentiment from at least one scout quoted over at Packer Update.

I have to say, I agree with a lot of what the Update both quotes and muses themselves. Harris was living on borrowed time by the end of last year. He can hang with some of the lesser receivers in the league, but when matched up with even marginally decent athlete's, Harris struggled badly. Not only that, McCarthy and Thompson have to be concerned with his absolute mental breakdowns against Owens and Burress. He was so highly strung for both those games, it affected his play, and that is just unacceptable from your supposed premier, number one corner.

I have no doubt, as the Update piece reiterates, that Thompson and McCarthy have seen on film the same deficiencies that this unnamed scout is talking about. I would not be shocked to see a corner taken on the first day of the draft for this very reason. (Though I still like Tramon Williams' upside...)