I guess seams actually play a pretty big role in stability :P. I was thinking about how you could get a knuckle ball effect with a perfect sphere, and that's what was bothering me. I didn't really think seams had that big of an impact, until I finally remembered that you can throw a knuckleball with a baseball.. then I looked it up and heh,
http://www.oddball-mall.com/knuckleball/mego.htm