I heard about about a similar (same?) method before and wrote about it here: https://ethresear.ch/t/optimizing-merkle-tree-multi-queries/4912 https://ethresear.

I heard about about a similar (same?) method before and wrote about it here: https://ethresear.ch/t/optimizing-merkle-tree-multi-queries/4912 https://ethresear.ch/t/optimizing-merkle-tree-multi-queries/... In the comments Vitalik links to his implementation.