All current research I"m aware of says there is no benefit to static stretching before exercise and there may be risk of microtears if stretching cold muscles.
Most aikido dojos seem to do a hodgepodge of range of motion, static stretching and dynamic stretching as their "warmups." I believe that good range of motion is all that is really needed. Nobody listens to me :-)
"I don't believe in it. You ever seen a lion limber up before taking down a gazelle?"
Sorry, couldn't resist.