Tender chicken legs

I was playing Trivial Pursuit last night, and a funny question came up :

"Which leg is the most tender on a chicken, the left or right? "

The answer was “the left one.”

Firstly, is this correct ?

If correct, why is the left leg more tender ?

I found this…
http://www.hsus.org/ace/11484

And this…
http://www.discover.com/science_news/mindscience.html

So it looks like yeah, some birds could be left-handed or right-handed, and so a chicken’s left leg could be more tender than its right leg, because the muscles that get used the most are the ones that will be the toughest.

But don’t bet any money on it, 'cause I can’t find any serious scientific proof, just factoids.