I don't doubt static electricity is dangerous. I just wondered what the problem was if I didn't plug in the computer to ground while I worked on it, but had my wrist strap clipped to the case. Even though the case isn't grounded, all that would happen is electrons would build up on the case right? Where's the harm in that? They would dissipate the next time I plugged the computer into a grounded outlet.
Electricity just wants to follow the path of least resistance to ground. The safest thing to do is just ground everything which in this case is you and the machine.
