I would have been more impressed knowing how often the engineers got out of the foam rooms and into houses, normal office buildings, trains, cars, and airport lounges using AT&Ts stock 3G nodes.
How do you measure interference? How do you improve reception if you have a half-dozen, dozen, or hundred arbitrary radiation sources? Maybe they missed the PR move with everyone else. Color me impressed.
Interestingly this prototype was wrapped in a case to make it look like the previous version of the iPhone, and the major problem with iPhone 4 is that when you touch the phone directly, as most end-users would touch it, you lose signal. The phony casing probably mitigated this problem, so maybe that's what happened there.
