[themgt]

First off you're I believe incorrectly using g rather than r in your "how volatility changes things" section. Secondly you seem to be assuming not only that r will be more volatile than g, but that it will be so much more volatile that medium/long-term r will drop enough to match g.

And lastly you're ignoring the actual history Piketty is describing, in which dynastic families very often tend to accumulate and pass on vast empires of wealth. When your speculative theory doesn't match reality ... perhaps it's time to reconsider the theory.