It looks like the iPhone 4 isn't the only phone out there with major death grip problems. Some videos are floating around of the HTC HD7 sporting similar issues.
The rule of thumb when it comes to "you're holding it wrong" is this: A strong signal isn't affected much, a medium signal can drop to bad, and a bad signal can be dropped at anytime. You would think something like this would have been addressed after the whole iPhone 4 fiasco, but sometimes things slip through the cracks I suppose.
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