Maybe, but neither of my 15" iMac G4s are that way. On the other hand, the 15" LCD is probably quite a bit less heavy on the arm.
Why? I think it's a gorgeous machine. One of Apple's most simultaneously adventurous and functional designs.
That said, I don't see any reason why you couldn't have the display and arm removed and connect a mirrored display to the MiniVGA connector in the base, but you probably have to have mirroring set up before you take the arm and display off.