The proof will be in the pudding. Whatever Apple announces today as their "fix" had better be conclusive and work reliably on every unit (except of course any with -other- unrelated individual problems).
If it's anything less than perfect, it'll appear as yet-another-whitewash, which would be incredibly unhappy for all.
I'm not an RF expert, I only dabble. I'll agree that the possibility exists for a software-only fix,... *IF* the problem is a software-only problem.
Long experience tells me that software cannot correct a hardware problem: it can accommodate the problem, it can mask the problem, and in some cases it can ameliorate the problem. But it cannot correct it in a true engineering sense.
I'll cross my fingers for Apple and wish them good luck, if this is the tack they take. But frankly I'm skeptical. I'm sorta hoping they own up to a hardware problem and correct it in a new release; people will believe that. And today, what people believe is Apple's biggest problem.
A software interaction would explain why the perception of low signal and the reality of few actual dropped calls is so different. And most of these cell phones today use no where near the power in watts that the older generations used, so it is mostly software on a very very low signal. Which is why none of the phone have the old radio style antennas any more.
These days with the way hardware and software are intertwined, you never know. 30 years ago I remember a geek practical joke running around about software being able to fry your CPU, and it was a practical joke because those who really knew the system knew you couldn't do that (crystal-based timing). Nowdays software can easily overclock your CPU or GPU and fry it.
Obviously, software can't fix an issue like the EVO 4G coming apart at the seams. That's pure hardware. But if the iPhone's antenna is software-controlaled to a large extent, it can be fixed. Apple was bragging about its new method of getting better reception, intelligently switching around and such, and that sounded entirely software. It also sounded very complex, the perfect place for a bug that causes the problem.
They announced that the free case offer was only for phones purchased before the end of September. That leads me to believe that a solution has been found and that phones without the defect are on their way with an ETA of before the end of September.