A Simple, Heuristic Derivation of our "No Backreaction" Results
  We provide a simple discussion of our results on the backreaction effects of density inhomogeneities in cosmology, without mentioning one-parameter families or weak limits. Emphasis is placed on the manner in which "averaging" is done and the fact that one is solving Einstein's equation. The key assumptions and results that we rigorously derived within our original mathematical framework are thereby explained in a heuristic way. 
Stephen R. Green and Robert M. Wald
gr-qc astro-ph.CO