True. The author is smart, and I would like to believe that he knew that reified unboxed collections would solve the space problem, but possibly be even worse

True. The author is smart, and I would like to believe that he knew that reified unboxed collections would solve the space problem, but possibly be even worse than Java in time, since there is no JIT to inline repeated virtual calls to the same target. I can't guarantee that he did. ;p