Did Concealment Of Prototype iPhone 4 Devices Mask Reception Issues?

We know that prototype iPhone 4 units were disguised to look like older generation units using some clever cases. And in theory cases like the one used prevent users from actually coming into direct contact with the iPhone 4 antenna points and in turn would prevent some of the recently reported reception issues. Now the NYT is speculating that the clever iPhone 4 testing disguise may have actually prevented Apple from noticing the odd antenna performance when the phone is held directly. [NYT]