Since then the result seems to be that stack vs registers, it doesn't really matter as much as people thought. A modern processor that's out of order [1] has to reconstruct the dependencies in the dataflow graph anyway. Out of all the things going on in a processor, doing so from a register ISA or from a stack ISA is not that different. A bare bones stack machine may be smaller than a bare bones register machine, but nobody wants to run those anyway.