Hmmm, just for purely scientific reasons, does a large busted woman have a potential advantage here? If the answer is maybe, I am not suggesting trying it out everytime such a woman is seen, you know, just for the science.There's SOME scientific basis here (I'm an EE). For those who care, keep reading... for those who don't, nothing more to see here :grin:
Keyfobs (and other handheld antenna systems) are designed with the antenna frequency to be slightly out of alignment with the desired frequency when sitting all alone. Human bodies are giant capacitors, and the idea is to design the antenna such that holding it in your hand "detunes" the antenna back into the desired frequency range.
Of course, keyfobs are commodity items... they are manufactured in the 10's to 100's of thousands, and manufacturers strive to cut costs wherever possible. This translates into some variability between each one. So while one may be +/-'x' in frequency, the next may be +/-'y'... and every meatbag holding the remote will be a bit different, too.
So, when the fob doesn't work as expected, people hold them up to their head. The "science" behind it is you are adding more "meat", and therefore "detuning" the antenna slightly more. The question is, are you detuning in the proper direction (i.e., more towards the desired frequency, or farther away)? That can only be answered on an individual fob-to-fob and meatbag-to-meatbag basis. Holding it to your chest gives you more meat, but it can also block more of the (now hopefully improved) signal. Holding it to your head gives you the meat without blocking too much (open mouth or not is irrelevant). There is a slight change to the radiation pattern due to your body, but that's negligible. Also, holding it 1-1.5' higher by putting it near your head instead of your waist is also mostly negligible.
But the short and skinny of it is, it can (and does) work in many cases. Hope that helps satisfy people's curiosity...