It certainly is rediculous crablord, you're in way over your head here.
Pens aren't used for stabbing! Why you got that idea, I don't know. Pens are to be used for grappling, for hitting nerves, for using as force multipliers in addition to regular strikes, and as an all around non lethal weapon that can be carried anywhere.
Heavy German steel pens can be swung around hard enough to fracture bones on the wrist or the fingers, in addition they can be used as force multipliers if striking pressure points such as the temple or adams apple, etc.
They can also be thrown extremely hard into the face of an opponent while you move in to throw them.
Pens hung on a string or cord can be used like a manrikigusari or even handcuffs. Have you ever seen someone get arrested by having their arms tied behind their back by a pen with a loop of chain on the end of it? It's the same idea as a tessen.
Clearly you are not on the right track when it comes to Japanese martial arts. I know that in various Okinawan karate styles objects the size of pens are used, I'd suggest you train a little longer to become more familiar with those objects before casting such a rediculous opinion of a useful object.
Here's some light reading material on the subject.http://www.e-budokai.com/hibuki/tessen.htm
Tessen and pens are the same thing for all intents and purposes.