It'll draw where your palms are as well. You have to be careful not to put your hands on the iPad.
Doodle buddy can handle multitouch writing. as in you can use up to 3 fingers to draw. So it is possible
The catch will be the developers need to make it so the first point of contact which is your palm is not the pen and then the second point of contact is recognized as the pen.
it won't be easy. Can I wear special gloves?