Is signal strength a factor in iPhone 4 antenna reception issue?

We've gotten a few emails this morning from TiPb readers who think signal strength might be a factor in the dreaded iPhone 4 "hold different" reception problems. Last night when testing at home, they could kill the signal by holding the iPhone 4 over the lower left side. When taking it out of their homes and onto the streets, it didn't seem to happen any more.
Could signal strength be a factor? If you're having the "hold different" antenna band reception problem, have you tried it outside in a high signal area yet? If so, any difference?
UPDATE: Jeremy says we should mention reports like Engadget's, where they get better reception with the new antenna. Jeremy is almost always right, so we're mentioning it. Bottom line seems to be: strong AT&T signal, and the new antenna does wonders. Poor AT&T signal and covering the antenna, there's no hope for you.
[Thanks everyone who sent this in]
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Rene Ritchie is one of the most respected Apple analysts in the business, reaching a combined audience of over 40 million readers a month. His YouTube channel, Vector, has over 90 thousand subscribers and 14 million views and his podcasts, including Debug, have been downloaded over 20 million times. He also regularly co-hosts MacBreak Weekly for the TWiT network and co-hosted CES Live! and Talk Mobile. Based in Montreal, Rene is a former director of product marketing, web developer, and graphic designer. He's authored several books and appeared on numerous television and radio segments to discuss Apple and the technology industry. When not working, he likes to cook, grapple, and spend time with his friends and family.