\tangent the early approaches were less efficient than later ones, meaning you need that much more power to get started, so you can start improving it. Theoret

\tangent the early approaches were less efficient than later ones, meaning you need that much more power to get started, so you can start improving it. Theoretically, the better method could have been worked out from the beginning, but actual progress doesn't seem to happen like that. It may be because a working model enables faster experiments (iteration) to search the space-of-methods faster, and in particular to prune off dead-ends, making the search-space smaller.