implement Aron's idea of interleaving the packing with the first computations
implement Aron's idea of interleaving the packing with the first computations

cjntaylor/eigen,pthulhu/eigen,pthulhu/eigen,pthulhu/eigen,pthulhu/eigen,cjntaylor/eigen,cjntaylor/eigen,cjntaylor/eigen,pthulhu/eigen