I have to press really hard (as in flex) on the band in both antenna spots in order to get it to degrade the signal. Obviously, I don’t hold my phone that way so it’s it’s basically a non-issue for me.
Location, signal reception, manufacturing differences (I’m sure the metal band is coated with something at the factory), skin differences, static electricity, etc likely explain why some can’t reproduce the issue.
We do know Apple knew the latest release of iOS 4 had reception bugs quickly after they released it. They told Mossberg a software fix would be out soon to fix the bar dropping issue he noted in his review.
It seems reasonable that Apple could tell the baseband to ignore specific noise coming from a certain antenna and/or switch to a different antenna. I find it hard to believe that the problem is an actual hardware defect. Surely Apple designed iPhone 4 to handle attenuation caused by normal hand holding.
And whether or not it’s an official part of the test, someone at the FCC, AT&T and every other iPhone 4 carrier in the world (all tested the device) would have noticed. Keep in mind, Apple doesn’t ship them units with iOS 4. They use a special stripped down firmware to do their testing.