The real confusion on this whole topic came about as a result of confusion about what was actually wrong with the antenna. The rubber bumper was Apple's attempt at getting this to become less of an issue, but it really didn't solve the problem. The problem wasn't in the hand touching both sides of the metal rim of the phone itself and thereby making some "electrical" short of some sort. That would be "solved" by the rubber bumper. But it wasn't for many - including me. It didn't work because the actual issue is in the position of the antenna under the hand "positionally speaking". If you cup your hand around a radio antenna you'll get less signal - period - laws of transmission 101 stuff. In the iPhone 4S they changed the antenna position to the bottom right corner of the phone so no hand could ever cover it - proving my point.
Again, the issue was the hand covering the antenna positionally not in the signal getting electrically shorted it out.
The only reason the bumper may have helped some people a little bit was that it raised the hand off the phone a few more millimeters thereby allowing more signal to get through.
In the end Apple realized their error and completely redesigned the antenna position in the 4S. I really love Steve Jobs for the great inventor that he was. But I was frustrated with him actually lying through his teeth to his loyal supporters about this antenna issue with the 4. It was the biggest "cover-up" in Apple's history; not to mention their biggest blunder design-wise.
